SharkeyMusic If I move away from the VL3X, what guitar + vocal FX processors with MIDI compatibility are people using successfully with Stage Traxx?
Guitar Processors I'm supporting/automating - Hotone Ampero II Stage and Line6 Helix LT. The Helix is a much older and physically larger device than the Hotone, but from a MIDI automation perspective, nearly identical in what you can do. For both devices I'm fully automating bank/program/scene/snapshot changes, turning specific Effects Blocks On/Off at relevant times within a song, etc.
Vocal Processors - funnily enough, I've spent the last 6 months researching this as I didn't want a floor-based unit (e.g. the TC-Helicon) but I also didn't want to spend more than about USD$400. For me it came down to buying a cheap and cheerful Behringer FX2000 3D 1RU multi-effects unit that lends itself to vocal effects, or learning to automate the built-in FX units in my Behringer X32 mixer. The latter was going to cost me nothing (except a lot more time), and save me 1RU in my mixer rack (and I didn't have 1RU to spare easily anyway) and because I use our X32 primarily as IEM mixer, I'd have to do some additional routing and patching to send a Vocal FX output to FoH along with the rest of our stage splits at gigs. Honestly, if you have the VL3X already and are happy with it, I'd consider keeping it and just using it as a dedicated FX processor!
I can't talk to any of your other migration specifics as my path into ST was different, but one trap many people fall into is trying to hold on to a lot of their original setup because they feel it will save them time in the transition, and they've obviously already made a large time investment in their existing setup, ironed out the kinks, and got it working (or adapted to the limitations). By hanging on to too much of their old setup, they create an overly complicated frankenstiein's monster type situation and don't manage to leverage the best of their old OR new environment.
In general, I would strongly recommend taking the approach of starting fresh in Stage Traxx. Look at all the functionality and map out what you want to use, and how. Factor in a future path to adopt features you may not want to use right from the outset so you don't paint yourself into a corner. Appreciate that you will likely have to alter some of your workflows in creating, moving, editing, sharing backing tracks/lyric sheets.
I don't know how you are automating MIDI currently, but with Stage Traxx 3, this part of the documentation is key - https://stagetraxx.com/user-guide/midi/
All MIDI events are embedded in the lyric sheet. Stage Traxx 4 (due later this year) will add support for an actual MIDI file containing controller events which will save time for those of us currently building everything in a DAW and then having to essentially 'export' the MIDI event data (basically a manual process) into lyric sheets.