I remember aerospace being rare and I think it should be. You need ground units to take the field. I don't think the bottleneck shouldn't be manufacture though. It should be in pilot training. If it takes longer to have ASF Pilots, wouldn't there be fewer ASFs?
Or rarely deployed. You wouldn't want to risk your flight corps on just any unidentified inbound dropper. The planes, themselves are also expensive to produce, so replacing them wouldn't be that easy. And, as has been pointed out in another thread questioning maintenance, Fighter Craft are maintenance Hogs, meaning that some may be stuck in a hangar at an inopportune moment because a circuit board is on the fritz, or the fuel line isn't injecting right.
The solution to that seems straightforward to me: Planet-based anti-orbital infrastructure that is common and effective enough to cover important infrastructure and make pure Warship-based orbital bombardment generally inefficient and dangerous, but not so ubiquitous and effective that Dropships can't land somewhere outside the anti-orbital defense coverage and deploy Battlemechs to attack such infrastructure.
Unfortunately that would essentially require a lore rework since Battletech's already entrenched into the alternative approach of "Fleet?" Distant Alamo Explosion "What Fleet?"
But, it would work well in an age where warships are limited.
I'm surprised that the IS powers allowed their navies to fall apart as badly as they did. Honestly, I'm surprised we didn't see some ship crews and captains turn pirate/privateer near the end of the 2nd Succession War. There may have been a time where individual warships would bounce around and be the force projection bubble for parts raiding.
And, if you only have ONE ship, it's priceless. You wouldn't stick around to see it wrecked or captured. So, the idea that many planets would turtle up with effective anti-shipping firepower near important points of interest would actually act as a deterrent for a solo Warship to keep its distance.
And, that would mean that having a single planetary defense warship or even monitor would also act as a means of keeping the Pirate with a warship or Merc with a Warship under contract, from sticking around too long. You get into that gunfight. you lose your mobile base of operations.
Thus you could have single ship-to-ship combat, but with a hefty forced withdrawal set-up. Having to play your escape because the enemy showed up just barely in time to get off a few shots might be interesting for those wanting to track that kind of thing with a merc/pirate force.
And, this goes back to the lore needing a bit of a touch-up. Would people be okay with that, though, in light of the 1st and 2nd Succession War source books that came out recently? You want warships in BT, they really need a presence in the fiction other than key moments in major wars throughout BT history. I'm not strictly drawn to BattleTech for the Historical Battles. I don't mind playing in historical eras, but the big draw is generating a custom force for the period and seeing how far they get, and what kind of impact they may have in the back yard of history in BT. That will be true of Warships, Aerospace and Dropships just as much as my star Mech Force and the hero characters I have in them.
The attrition rate must certainly be higher. Ammo explosions and headshots aside, mechwarriors tend to survive combat, and mechs are easy to repair or at least scrap together. What's left of an aerospace fighter after a failed lawn dart roll?
Y'know, I've read through the AT2 and TW rules for aero a couple times and have played a variety of missions with Droppers and AeroFighters. But, there's one thing which escapes my memory: Pilot Ejection. I don't recall if there's rules for emergency ejections for Fighter Pilots. There should be. It's a key feature in modern combat avionics. It's an intrinsic part of BattleMechs.