Personally, i'd rather just have my army circle the hideout (hey, if I can park 200 guys just outside it for 24 hours without them noticing, then surely I can surround them?) then forgo the 'bring ten random men' thing and just devote 60 guys to preventing them from running away, then send 50 more guys in to mop up.
The whole thing about them slipping away if we don't try to stealth is is easily negated by just surrounding them so they can't escape.
There's really no reason to play by their rules, especially when a bandit hideout can have 40 people in it.
Asking me to take that on with ten random guys from my party is completely unreasonable.
Adding a troop selection screen would help (and frankly feels like a mandatory addition) but enabling you to just use your superior numbers to prevent them from running away would be nice.
Maybe have it locked behind scouting/roguery or tactics? And troop numbers.
Say it takes X amount of troops (30?) in order to encircle them and make sure they can't escape, and doing so requires a skill-check to see if they slip past you. (which causes the hideout to go into lockdown where you can't attack it for several days) but if you succeed then it removes the troop-cap on how many people you can take with you and you get to send in as many people as you want to stomp them flat.
Alternatively, you could just give us the option to burn the whole hideout down, which forces the entire band of bandits out onto the world map in the open, where we can engage them with our armies.