note for those that don't have sta - The second best evp armor is essentially free to get anytime, Stealth Suit is available in Gallon's Plan for 10-20 photon tickets (there's 3 items for 10/15/20 but I don't remember individual price offhand) from an npc in town (quick forest quest, 2 tickets per run on vhard, if you choose to side with npc at the end instead of gallon). It has no resists, 1dfp, but has 300evp making it second most evasive armor in the game, even more so than samurai armor (277), or wedding dress (244-284). It also makes weapons switch instantaneously, so bullets can't misfire. Though it does make items on ground harder to see as you can't see objects through your transparent body.
However, in practical terms if you aren't playing one of high evp classes (ramarl/hucaseal mostly), then trying to attain high evp is kinda pointless, as most chars don't have the extra room to raise evp anyway in addition to have significantly less to start with. Likely better to just use Traps on a cast or rabarta on a force rather than boost evp in most cases.
Humar is only class that doesn't have traps that could theoretically boost evp a lot, through extra mat space (maxes at 786 for char stat), and through Proof of Sword Saint (with specific katanas, sabers, twin swords, and two kamui) and his 3 free slots (+60evp each, technically higher than ramarl if geared out), though I think only excalibur and orotiagito/raikiri would have aoe potential
As this strat is essentially just 'kill lots of weak monsters in high level areas', you can use whatever strategies you feel most suited to, even going full nuke force can work ok enough for just a few rooms like this.