IMO, the obvious short-term improvement would be to simply allow you to hand-pick the troops your bring with you to the hideout. This has already been mentioned a few times and I totally agree. There are many advantages to this approach:
- It should be reasonably easy to implement. The UI for this already exists (it's basically the same as when you send a companion off on a quest), and it doesn't require the hideouts themselves to be redesigned.
- It provides a meaningful choice for the player. Loosing because RNG sent you off with 4 recruits just feels unfair. By giving the player control of the party composition, you introduce an interesting problem of finding the optimal troop composition for each type of hideout, constrained by what troops you have at your disposal at the moment. This is an interesting challenge for the player.
- It doesn't trivialize the hideouts late game. If you, for example, are allowed to bring your entire army to the hideout, they would be of no challenge whatsoever beyond the early game. 9 Legionaries vs 30+ Sea Raiders is still a decent challenge late game.
While the other, more ambitious reworks suggested in thread are all good and fine, I'd go with this suggestion because of its simplicity.