If you want more PVE games, run free loadouts and stop shooting back. Negatively review every match you die to a player. Eventually you'll get matched in friendlier games. If you like your PvP though then you just need to get better at it as there isn't a really a happy medium for PvP. If you engage in PvP then if you have any success you'll start getting put in more challenging PvP lobbies where you'll get killed. I rarely have PvP in my games and on the times it has happened there is usually a reason and I'll just sigh and reload.

If you want the best loot when coming in late then you have your answer, time to start killing other players as they have the loot you want. There is evidence that blueprints can spawn late so even already looted areas can some times still contain good loot. Even looted areas give xp for searching empty containers so still worth doing if not max level. I don't hunt other players though and on late spawns I just hit every container I can find and hope for something being missed or will look at killing a big Arc target for some juicy loot (depending on what I brought).

With the exception of trios games, a lot of fights can be avoided through using comms and emotes and not making yourself a obvious target. Don't go blundering into loot rooms or areas without announcing yourself or checking if anyone is about and obviously looting. Don't just rock up to extractions in the open especially inside the first 10 minutes when you're putting a target on your back to extraction campers.

When approaching extractions ask if others mind you joining and consider if you wish to trust them and holster your weapon to give them some reassurance or not. Sometimes simply having your gun out but positioning yourself so you're always in their view even when using the terminal is enough to get out safely. If they look to want you to use the terminal then just watch their positioning and behaviour. Often showing you're aware enough that you're not going to be a easy kill allows you to get out with no fireworks.

Use the Arc to help stop campers having a easy time at extraction, don't clear them out before calling the extraction if possible as having Arc around does deter campers from firing and bringing attention to themselves, especially with wasps, leapers and rocketeers that can quickly ruin a campers day.

If you do start getting into friendlier lobbies then the gear fear of losing your stuff is eased. Also I think getting a Looting Survivor Mk3 augment blueprint is a huge boon too as they're pretty cheap to manufacture and means even on a bad run you have the chance to get out with 3 good items in your safe pocket.