Either alot of cruisers or 4 battleships + cruisers. Depends on the faction the missions are against. If it has battleships, they might spawn, if not, you will face around 12 cruisers.
Probably. You'll likely get cruisers or something. Though it depends on where you're taking it, what faction you're taking it from, and what faction you're up against.
Sometimes cruisers sometimes battleships. For example u can take 5 million outcast mission with 4 wave of Bullheads and see no BSs. Or take 3 million mission with 4 Battleships
Eta, for example, you may encounter 11 cruisers + 2 legate/osiris
Alpha you may encounter all Bullheads, threshers, mako's or a (un)healthy mix of these
Gamma is pretty much the same as alpha.
Alberta (rog missions) you can run into 2 Labc + 2 siege cruiser waves then 3 LN dreads following shortly after.
These are the missions I am familiar with, however there are many other combos, depending on location.
My suggestion to you sir, is to bring with you a friend in a cruiser or higher. That should be enough to farm 100m+/hour doing missions
Generally, they're all cap ships. At the very least a gunboat.
Protip:
Get pals in Nova bombers and raep the enemy.
Also, get a transport along to scoop up pilots. Some pilots might sell well on nearby bases.
Eg: Outcast pilots sell for around $10 000 at Dounby in Orkney.