They don't give bounties per se--They drop 'blue loot' that has set NPC buy orders. Each C4 site averages to 95 million per site with about 50-60m from blue loot and the rest from salvage. The frigates and cruisers can be salvaged quite easily with Salvaging III and some T1 salvagers. The battleships are a little harder to salvage so might require some Salvaging rigs.

I personally run a command ship which provides links and does the salvaging for me. It's a nice package deal and safer/faster than trailing a Noctis behind to salvage.

From the perspective of isk/time as a multiboxer, I firmly feel that Incursions are the best place to be followed somewhat closely by a C4-C6 wormhole. My characters are still low skilled (5-6m sp per toon) but once you get an effective UI and ISBoxer setup going it's pretty easy to clear the C4 sites. The majority of the risk is getting discovered by a larger WH entity and them forming a fleet to come fight you--However, since you're in a C4 it means they're not bringing in a capital fleet. If you've got 10 ships in your fleet, you're going to scare off most people

From a fun perspective I enjoy the WH life, though it can't be stressed enough that the logistics of living there suck. I have almost an entire backup fleet of ships in my POS because you've got to stock up when you have a good high sec exit. I'm currently mulling the idea of running 20 man Incursions for money. If it's twice as fast as what I can do in a WH... Yeah, the boredom might be worth it