not important anymore.
XT is laded with knobs, 44 of them no? So you could live without… but… makes stuff a lot easier, especially with regards to wavetables.
You could check out monstrumWaveXT from Monstrum Media
Note: I use my own stuff and things, so can’t comment on anything / any one else(s). In the past I used EMagic’s SoundDiver, but a long time ago.
XT owner here too
i don’t think i’ve ever used a dedicated patch editor for it apart from SoundDiver mentioned by @Rusty; the XT has plenty knobs for editing but yeah, one comes in handy for wavetables and maybe storing those extra patches…in case the internal memory isn’t enough
XT owner here. never felt a need for anything beyond the many knobs