It's all RNG for weapons, basically once you're done, you get just a bunch of random weapons. You get a certain amount of gold boxes(for the highest tier of weapons), a lot more silver boxes(for purple weapons) and then a bunch of copper boxes for the lowest tier weapons. It's purely RNG what type of weapon you get, or which weapon within each category. They range from hot garbage to best weapon for a specific playstyle. If you like changing weapons it's great(especially if you haven't checked the weapons yet since you can get some really good shit without having to farm nergi/vaal hazak/deviljho for mats) but if you're only focusing on one, getting the stuff you want pretty much suck dicks. You also get an armor set which is ok-ish, the chest is very good and some of the other pieces are useable, that's crafted the normal way using the materials that drop during the fight.
On the fight itself, there's a bunch of optimizations you can do if you want to farm hardcore, although I assume a lot of pubs are just going to be running around doing shit slower.
The main tip is bring Partbreaker 3, it's easy to get 3pt(can get a piece of armor with 1 like uragan belt and 2 from charm, or 2 from armor like uragan chest and 1 from a jewel if you have one or whatever you prefer). Since Kulve is entirely about breaking parts, once you break all the stuff, she flees and the fight ends, regardless of damage done, Partbreaker is effectively a 30% damage increase on this fight, and there's simply no other skill that gives nearly that amount per point.
Another recommended one, but more for static groups than pubs, is Bombardier 3, to make use of barrels. You can barrel her a bunch to get some free damage in on the horns, especially when you sleep her(LBG/HBG with sleep ammo is great for that). Her sleeping animation is so long, you have time to run in on her right paw, drop 2 barrels before she's done falling asleep, then detonate them as she lands, so you can craft 2 more barrels and bomb her again while she's sleeping. In this situation, having Bombardier 3 is a pretty big boost, although it's less necessary overall.
For cheesing the fight, the "best" way is using an elemental LBG setup. LBG comes with various status, does high elemental damage, can hit any parts at about any time since it's ranged, so it's just great. The best setup on PC currently is something like this:
MHW Builder with a switch for Phase4 to Daora stinger and cold damage instead of lightning damage. It discards pointless stuff like Weakness Exploit(with a LBG the only weak point is the main body, which isn't a breakable part, aka completely worthless, so WE never procs) and just focus on breaking parts. Also a healthy dose of defenses(20fire resist base so you're immune to burning, 3health gems although 2 without the augment is probably less retarded). I'm not entirely sure if you need WE on phase4, you could fit it in probably. Bring ammo+materials to make more ammo and barrels+materials for barrels and a farcaster to change gear for phase4(most people do this regardless).
Mind you this is optimized shit aiming at easy clear/static group farming and what not. You can just bring whatever to the fight it's not really hard or anything from what I've seen. Just get lightning for P1-3 preferably(she has super weakness to lightning), partbreaker to break shit and farcaster to change to raw or frost for phase4. There's also cannons you can shoot(can get Heavy Artillery for that), stalagtites to shoot to do big damage and in the last room there's a bunch of pillars and shroom walls you can climb on to spam aerial attacks to do big damage, so you can definitely do whatever you feel like.
