Sabotuer Vortex Trapper

Hello im making a Vortex Trapper and i'm about to clear cruel but i feel my damage is low and cant seem to get my resistance up what should i buy or spec in to to get my character ready for merciless and maps
i have about 300 c and 2ex on standard so any help would be appreciated this is what i have so far.









https://www.pathofexile.com/fullscreen-passive-skill-tree/AAAABAYDAQW1Bx4I9A5IES8RlhvgIvQj9isKMHEwfDGzMhg2PTpCRXxJUUt4TZJRR1MxVEdVS1b6V9hd8mHiYk9irGSqZ05qNmwIbAtsjG0Zb3dwUXZvfrB_K3_Ggh6IQow2jX2Nv5ANkyeVLpeXl_Sbhp2qnsSmvrMDtDi0xbd1wcXC7MkG1CPYVNsL2-fdqOUZ62PsGO4V8NXxivv1

Well, where to start. I don't really know anything about the build itself, but some gerenall stuff:
The resists problem is most likely due to your belt which gives -all res instead of +all res (you might have misread that). Furthermore, the gloves and boots are pretty terrible, pretty much of defenses at all. Timeclasp is pretty bad, Astramentis pretty bad for anything other than Stat builds (such as Whispering Ice) and leveling. I would start there. With your Budget there should most definitely be WAY better options out there, i.e. more rares, less crappy uniques.