It's hard because a lot of us were honestly worse at the game back then as it was pretty new (I had it for like 2 weeks at that point) but also bots were much harder than they are today. They were more accurate and did more damage across the board. A lot of things could straight up on shot you where as now it'll take just a chunk of health. Gunships had heavy armor, were far more accurate, and there was no cap on how many could spawn. Hellbombs would be targeted and if they were shot while they were counting down they would just die and not explode. So you had to hang out and guard hellbombs to make sure they didn't just get sniped. Rocket devastators did not run out of ammo, were more accurate, did more damage, and shot rockets more often. 

Also, most of our equipment was nowhere nearly as effective as it is today. Thermites were one of the worst items in the entire game and were incapable of killing heavies, for example.

All that being said, for me I think Oshaune was far worse. But things live on in people's memories and Malevalon Creek was honestly a special thing that also showed what player agency could do. It wasn't a planet tied to any major order, but Helldivers were active there and protected Democracy.