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...and here's the thing. I ALREADY have that technology. And it works. Has always worked. And continues to work.
In my games, you don't have to be in orbit or deal with any of the hassles that makes it hard to play. You see a planet, you can dogfight and fly around its orbit all day long and NEVER enter the planet by accident. In order to do that, you have to target the planet and press a key to initiate a planetfall transition. When that starts, the engine switches to an external camera - you enter the planet. Land. Get out of your craft in first person mode.
Ah, but part of the appeal (to me) would be that you COULD, if you so wanted, move from space combat area of engagement to atmospheric flight, or land, or disembark your vehicle, all continuously without activating a planetfall cutscene or anything like that. And also if you were not careful, you could end up burning in the atmosphere if you overstressed your craft... or if you dropped too low in a space craft not qualified for atmospheric entries. It would be largely non-issue if the player started at 36000 km altitude at geosynchronous orbit; for all intents and purposes, orbital mechanics wouldn't really disrupt combat there.
It would also introduce some pretty interesting dynamics to the space combat, since you could then have spacecraft that are capable of only spaceflight but be more optimized for space combat (lack of wings and other accessories required of airplanes reduces weight), vehicles capable of both atmospheric and space flight, and airplanes that would only operate on the atmosphere.
The way I see it, space combat would be concentrated on a very small areas - mainly, stations on geosynchronous orbits and Lagrangian points in the system. Players interested mainly in space combat would be deployed on these areas, however it would be
possible for them to traverse to the planet's surface if they so wanted. Similarly, people interested in atmospheric flight combat would be spawned either on air starts or airfields depending on the mission, but if some hardcore player really wanted, he could pick an space flight qualified airplane, get into orbit and attack the enemy capital ship on low orbit. Or a flight of ground attack craft could undock from that low orbit capital ship, descend to the atmosphere and commence a ground attack. Being deployed on the immediate vicinity of action would make the game accessible to people who aren't intersted in long sessions of simple transition from place A to place B, but continous game world would make that possible too.
...or you could have orbital drop shock troopers (with another name to avoid trademark conflicts

) seamlessly deployed from low orbit to surface. Or you could have a transport pilot delivering a Marine squad on a space station, or other endless options.
Myself, I would prefer to fly single pilot craft in either atmospheric or spaceborne ship-to-ship combat, but the option where you would be able to gather my survival kit after crash landing on enemy territory, and try to avoid capture is sort of interesting too.
Regarding form of combat, I'm sort of torn. I personally greatly prefer visual range gun combat (aka dogfighting) to BVR missile fights, but on the other hand it might be implausible to exclude missiles altogether. Perhaps making them a commodity might work best; that way you could both make them plausibly destructive and explain why there aren't too many of them.
...and although visual range swarm missiles are visually stunning, I don't think I would want to deal with a
Macross Missile Massacre being unleashed on me...
