May i suggest lowering fleet cap costs and/or the percent it takes away from all ur incomes.
Yes, lowering the upkeep is probably a good idea. Keep in mind though, there will be research that increases your resource income, so it'll rebalance things a little and speed up building. But don't forget that BFG has never been about huge battles with 60+ ships, but about the tactics with a 3 or 4 cruiser and a dozen escorts. (and that's a pretty massive fleet on the table.)
That doesn't mean you can't build huge fleets. I've found you can quite adequately handle 50 ships in a battle and still maintain some sence of control of your army, instead of it turning into a massive mob. (courtesy of the dev.exe I have no idea how long it would take to build that)
In the "testing" bit of my post:
Bombers often seem to overshoot their target, not shooting on their first pass. Any idea as to what's causing this?
oh god dont tell me about a new space sim i just pulled myself out of X3 if you show me a new one especialy one i'm slightley interested in the background of i'll well i'll dissapear for a rather long time.
Oh, don't worry, it's only two levels in the release

PS: BTRL rocks. Can't wait till they release more missions.
PPS: We still need someone with a little drawing/photoshop skill, to do the ship icons (the ones you see when zooming out) and construction buttons. Seeing how we're not allowed to "borrow" the images produced by GW, we need to recreate them, or something like them.