I've purchased a few materials packs using crystals, nothing using money, and I'm at L45 and hitting 80% on t4. But I haven't purchased anything like all the packs available. My crystal spending has been fairly restrained. I've maybe spent 2k over this entire era so far? That's a guess, but it wouldn't be far wrong.
Which leaves me in the interesting position of being 10 levels above you, but 10 behind Darjelo. Am I doing some things right and others wrong?
It's so hard to know. But even more than that, it's so hard to know what is ultimately crystal-efficient. Most of what CG intends to give us is a combo of r10 mats on a day-to-day basis and g1-g12 gear at the end of the era.
I don't need any gear below r13. All my toons are relic'd and I have plenty of gear sitting around to do the same to new toons. I won't need it now, but it also isn't a benefit to me.
So mostly I am spending now to get more r10 mats, but how many will I need. how quickly? Should I have been spending more to move up a reward tier in r10 mats?
Who knows. We really truly don't have enough information to evaluate the best value for our spending, much less how much effort will be worth it. We'll need several cycles to begin to optimize this stuff.
Worrying about getting better is a good thing in moderation, but don't let yourself stress too much about it. It will get sorted in time.