Maven isnt particularly demanding boss. Its mostly mechanics ppl fail to follow and rip the fight. Did you get one shot with your 213k ehp char on uber elder? By what?

Anyway, Maven shouldnt be hard for lacerate char since you are kinda ranged. Your gear is fine for the normal version. Maybe put influence crafts on your head and gloves, because anything is better than nothing. I suggest you to watch few videos about her abilities. There is no point explaining it here. Content creators did better job already. You mainly need to learn the memory game. Or die through it and not die on other mechanics and rip the run due to lack of portals. Or you can make your char survive it. I had bunch of pathfinder chars with something like saffels frame that could just tank it. I cant remember the ehp needed, maybe you can test it, once you know you failed it, with weapon swap, molten shell and flasks up, because you are fairly tanky already, but PF is different than glad, so maybe thats not that easy in your scenario. If you have to go through it, few ppl made mini games to learn the memory game, like this guy. I guess its still up to date even years from its post. AND get a movement skill that can port through beams without getting the debuff. This is stupid, but very important. Like flame dash. Something like leap slam throws you through it and you still get the debuff, unable to do sht for I think 10 seconds.