Getting rid of Abyssus without losing damage...on budget

When it comes to knowing what's possible in PoE, I'm still learning things. So now, I need a bit help with figuring out what's possible in my situation.

Abyssus was a great damage boost for me, especially since I found a nearly perfect one. But it's also becoming a liability since I don't have enough damage to simply wipe out everything on screen, especially during boss fights, and some nukes or degens (even with staunching flask) just get through.

So I need to replace it in the next round of gear upgrades. But how exactly, on my limited budget, that's the question.

ATM my budget is 3ex+200c, or 7ex+200c if it'll include a good boots with "cannot be frozen" prefix (which is 1ex by itself, so not worth putting on cheaper boots).

The build:
https://pastebin.com/JyT8jYYi

Edit: forgot to switch off some things to give the more accurate sense of the build's capabilities. New one up now. Switch to sand stance and onslaught on to see mapping performance.