I discussed this at length with a few people in the Homeworld community. The general units used in the first two homeworld games are generally accepted as feet, based on this picture:
This door is visible on the side of the Taiidani corvettes. The door is six "units" tall in game. Either the door is 6 meters high, or around 6 feet high. Same deal with the Kushan corvettes: They're all two seater craft and the ship guide mentions that every corvette interior is so cramped that a mechanic must seal the pilots in with an armor plate from the outside. If each corvette is a hundred meters long then the canopy glass is several stories tall and each cockpit is the size of a bedroom on smaller craft. It doesn't fit in line with some of the official concept art.
In Homeworld 2, the units are meters based on one or two common ship model files and comments from Relic itself. There's an option to make the ships actual size in the command line, but doing so makes bombers and fighters nearly invisible except for their trails.
The reason I felt that the ships were larger in Homeworld was to make it visually easier to comprehend, select, and move units.
This puts most fighters and bombers in the 15-20 meter range, and corvettes around 30-40. The Salvage corvette is 35 meters long.
That being said, this doesn't scale well to capital ships. The Taiidan heavy cruiser is 1400 units long - which means at the same scale it is in the game, it would be around 450 meters long - not even twice the size of a Fenris. The mothership would be the largest thing in the game, but it would still be smaller than an Orion stood on end.
I decided for "realism" sake to scale units for corvettes and strike craft down to feet (there's no way the kushan scout is 50m long) and the larger vessels for units to meters.
The multibeam frigate in that screencap is 220m long, smaller than a Fenris. The Turanic Carrier, which I imported yesterday with a ton of turrets, is 2400 meters long. Taiidan heavy cruiser is 1400, Kushan heavy cruiser is 1300, etc.
The mothership, however, will be the size of the colly
After all, it has a population of however many staff it, and 600,000 more in cryo.
Hopefully the scale ends up working well, but the conversions I do are my own take on the Homeworld Universe. While TAP is going to be using some of the models I converted over for the test builds until new ones get made, this little project of mine is something separate
So yes, you will be able to fly all the strike craft in the game.
