Minimum of 20 seconds respawn delay after your dragon is killed. Then the cost to spawn it starts high and scales down the longer you wait to respawn it. EXAMPLE: If you wait 21 seconds it costs 100 followers. 30 seconds reduces it to 80 followers. 40 seconds reduces it further.
I agree that the Dragon needs a respawn timer if it's killed, something like 10-15 seconds. It doesn't punish you enough for dying as a Dragon, or reward you for killing the enemy Dragon. I do think that 20 seconds and 100 recruits is way, way too much. It will basically kill the use of the Dragon entirely, because that's a lot of recruits that you won't be able to spend on units.
The Dragon is powerful, but not powerful enough to make that cost worth using it.
You should only be able to despawn your dragon after you have not taken damage for 10~ seconds.
After watching the Octaaf/Lorean match, I agree in part. It was really easy to shift safely out of Dragon form in the middle of combat as long as friendly units were around.
10 seocnds seems too high, 5 seconds max, maybe even lower. I'm not sure what the time should be, though.
There should be a button you can assign for the fastest possible "Rapid fire" you feel is acceptable to game balance. Remove the "clicky" mechanic for rapid fire. Leave LMB as a "maintain" fire.
I totally agree about not wanting to rapidly click my mouse to fire. The fire rate from holding the left-mouse button down should be increased to match the rate from rapidly clicking it. I don't think that any further balancing tweaks are needed to bring holding into line with rapid clicking, but if Larian thinks that letting you hold for continuous fire is really, really too powerful for some reason, they could increase the rate at which the hold-button firing over heats.
Finally- I think you should only be able to pick one fight your dragon can attend per turn.
The one-dragon fight/turn limit is in single-player already, but it cannot be changed in multiplayer. The reason is that you can't have some players enter RTS mode to fight as a Dragon and others sit around doing nothing - it doesn't work. If anyone wants to fight as a Dragon, then the game has no choice but to force all players to fight in RTS mode as a Dragon.