[Erebus Alpha]

Currently in my mod, ships and projectiles fly a lot faster than in the retail game. I did some testing, and both the AI (and myself) manage dogfighting and maneuvering at 200 - 300 m/s quite well. Some of the interceptors can get up to 400 m/s with afterburners. It's also nice when capital ships glide across the screen, instead of creeping along like giant snails.

I played through the Freespace 2 campaign, to get better acquainted with the Freespace 2 story, as my mod will occur in the same universe. Minor details of a few of the missions in Freespace 2 will be really important in my mod. However, there is a really sharp and apparent disparity in Freespace 2 vs. my mod, in terms of flight speed and distance scaling. I knew this would be the case, but Freespace 2 seems like slow-motion.

Are Freespace 2's interceptors really supposed to be afterburning at velocities equivalent to propeller-driven aircraft? Are bombers literally supposed to cruise around at speeds no faster than a low-grade sports car? Was Admiral Koth literally supposed to be ramming the Colossus at his ship's top speed of 15 meters per second, or a whopping 34 miles per hour? These all seem unlikely to me.

Or, are these spaceships supposed to be moving at speeds equivalent to aircraft? Are interceptors actually supposed to be maneuvering like jet fighters, and Freespace 2 just sort of glosses over even the slightest semblance of reality? The higher speeds do make dogfights tougher. Was worried that the typical gamer might not have fun in a more challenging environment?

Weapon convergence and a very slight auto-aim are two features that my mod would probably be unplayable without. This way, hitting a distant speck does not require superhuman aim. Did these features not exist in retail FS2? Has the modding community allowed us to outgrow the arbitrary speed restriction necessary to make the game playable and fun?

To speed or not to speed - that is the question. I don't like the visual aesthetic of capital ships creeping along painfully slowly. On the other hand, I want to avoid hitting players in the face with a giant shovel as I introduce them to "This is how fast the spaceships are supposed to go" - especially if it's inaccurate.

[General Battuta]

There is no way to make physical sense of Freespace combat. It's just built to be fun. Faster ships aren't any more or less realistic - there's nothing more plausible about space dogfights at a few hundred m/s relative than a few dozen. So treat it simply as a choice about how to present your gameplay! Do what's fun and right for your mod design.

One reason that FS2 keeps the speeds low is that this makes the action faster. Ships can engage up close in tight turning fights, with a lot of decisive attacks. As relative speeds increase, you get less time near your opponent and the action slows down a bit. Check out Diaspora for an example of an awesome flight model with higher speeds - note that you don't really get up in the enemy's grill and dump missiles on them. Instead you take a lot of deflection shots.

[General Battuta]

And no, retail didn't have convergence or auto aim.

[Droid803]

Realism and Space Fighters do not go together. It's not the slightest bit realistic, regardless of your top speed - top speed is an atmospheric thing.
In real space, there is no maximum speed - you can accelerate in one direction for as long as you have fuel.

So no, top speed existing (and set to what it is) is purely a game design choice.

I've done (and released) a full mod with high speeds/weapon convergence/autoaim like you mentioned (see: Dimensional Eclipse) and it plays very differently from base FreeSpace, but I don't find either flight model to be inherently superior. I actually think the base FreeSpace model actually requires more skill that blasting around at high speeds and relying on autoaim/converge to actually hit things. These two features which are kind of necessary as you noted actually detract from some of the intricacies in basing FreeSpace dogfighting where gunmount positioning and target profile matter a lot. With converging autoaim (however slight), these suddenly become non-factors and its really just boiling down to # of guns vs. shields/armor and getting out of the target cone for autoaim. Without these, dogfights are exceptionally difficult for a human player (the AI has no problems hitting you without autoaim no matter how fast you go, though)

[General Battuta]

The most fun part about the Diaspora/Dimensional Eclipse/etc flight model is managing your momentum. In FS retail physics you don't really 'commit' to a direction - it's easy to turn around and go the other way. But in high speed mods you can build up a big vector in one direction and it can take some real work to change it (say you need to dodge flak).

This is one reason high speeds can create slower gameplay! Your direction of travel is less dynamic, and you have to think ahead about where your vector will carry you.

[FrikgFeek]

Retail-like freespace gameplay has very fast turning, acceleration, but rather slow top speeds. This creates gameplay that's very different from ~WW2 atmospheric sims while still keeping a similar "close and personal" feel. Who gets behind who is decided by half a second difference in when they start turning after a head on pass. This is much more noticeable in mods like WiH which use Fury AI and enemies with actually dangerous weapons rather than Shivan peashooters. Quick turning and quick kills mean that even slight errors in timing lead to a mission restart, at least on insane.

High speeds create gameplay that's a lot more focused on distance, as by the time you complete that turn the enemy fighter might be quite far away.

This is similar to atmospheric jet sims that are somewhat realistic but not full on simulators, taking down a fighter relies more on projecting their movement and thinking ahead to get a good angle behind them than quick decision making or reflexes. Which you find more engaging and which you'd like to use for your mod is, obviously, entirely on you. Just don't get hung up on any kind of realism.

Also if you create extreme speeds and fast turning fighters you might make it near impossible for the AI to hit the player using autoaim, as they will always aim at the lead indicator, the place you would be if you didn't turn. You might also want to make the weapons much faster to avoid that, otherwise any kind of continuous motion will make you unhittable beyond knife range. This is also somewhat a problem when facing AI classes with very high accuracy, as they'll keep shooting at the only place you're guaranteed not to be.

[Erebus Alpha]

Generally, the weapon projectiles in my mod do fly much faster - typically between 2000-3000 m/s.

Interestingly enough, I ended up having some fun and unintentional gameplay: The Terran fighters' only saving grace is that they generally have a lot of firepoints, whereas the Vasudans have ships that can accelerate, decelerate, turn, and afterburn more aggressively. The Shivans have far better weapon technology, limited only by energy usage and the player's ability to hit stuff.

I think I'll keep the high speeds. The gameplay is uniquely dissimilar from retail Freespace 2, and it offers a different challenge, and it passes the fun-check. Although the flight model is not realistic by any stretch, at least there is the sensation that a capital ship's thrusters are powerful enough to carry it out of a planet's gravity well.