Shortly before the launch of each of SWTOR's past (story) expansions, I always made a post about my plans and expectations: Rise of the Hutt Cartel was pure hype, though in hindsight it's quite comical to read about how concerned I was about there not being enough new sources of XP to guarantee a smooth levelling experience. I was also excited for Shadow of Revan, though a little bit of uncertainty started to creep in there as we knew a lot less about that expansion than we had known about RotHC pre-launch. And KotFE? Well, I was still excited, but also a bit nervous about the big upcoming systems changes, and that's pretty much how I feel about KotET as well.
(On the plus side, I've decided that no matter how that whole Galactic Command gearing thing goes, I'll be guaranteed to get some good blog fodder out of it. I'm planning to keep a diary of my RNG box contents for sure.)
I've been thinking about what to do to "prepare" for KotET but keep coming up kind of short. Some of my guildies are talking about choosing new mains based on the currently available information in regards to which class will do the most dps, but that's not for me. I've been Shintar the Commando since launch, and if things ever become so bad that it feels like I can't play her anymore, I probably won't be sticking with the game for much longer!
Alts are trickier though. Specifically, KotFE taught me that the best-laid plans of mice and men might still not work out as expected. Even though I had made a point of "preparing" certain alts for KotFE by making sure that they had done all the main story content up to that point, my Sage and Sorcerer for example haven't even stepped into KotFE to this day, they just hit 65 through doing other content. The thing is, the moment I played through chapter one and refused to kneel to Valkorion on my Commando, I immediately knew that I wanted to also play through this on a character that would accept his offer and for that to make sense in my head it had to be an alt that was very different from any of the ones I had actually prepared, which unexpectedly catapulted my rarely played Marauder into the position of what effectively became my "main PvE alt" during this expansion. Based on that, I don't feel like there is much point in trying to get any more alts KotET-ready than I already have. I do have four characters that have completed KotFE and are therefore ready to jump into the first new chapter right away, but based on how things go there the first time around, I might well feel an urge to suddenly dig up a completely different alt next. You just can't predict that kind of thing while trying to avoid spoilers.
That only really leaves me with the task of spending as many of my old crystals and commendations as I can before they get converted to credits, both because there is a cap that I'm likely to exceed on several characters and I don't want my currency to vanish into nothingness, but also because credits seem comparatively easy to come by so it's hard to imagine it being beneficial to choose plain conversion over actually doing something useful with that currency right now. If you're lazy like me and/or bad at maths, this page makes it easy to calculate how many credits you can expect and whether you're currently over the cap.