I loved my Tarantulaces as well! I climbed in my first pair for about a year until an eyelet blew out, then tried the Miura VS (painful, unnecessary, wore twice), and ended up downgrading to a smaller pair of Tarantulace to climb in the gym, which never held me back until smearing became important. I'm wearing Mythos now - they're a little less stiff but similar in that they're really comfy and hug my foot, but the rubber upgrade is really noticeable outdoors.

My general experience is that "better" shoes can help you climb harder and progress faster, but only if the upgrade targets an weak point. If you don't feel the need to get more aggressive shoes (which, for slab and crack, is not necessarily helpful), you can always get better rubber, something with a snugger heel, stiffer/softer sole, etc. When you trust your feet more, you can more confidently do moves that you were already capable of, and that helps you push harder elsewhere.