I have noticed a change in trans stone drop rates from rewards of the worthy. This is only just my observation. The rewards, on the other hand seem to be improving (slowly) which is a little more obvious.
OP is talking about leaderboard rewards rather than your post-match reward or RftW. I got an Impregnable Armor precise restoration staff this weekend. And 5 transmute crystals. Only got leaderboards for flag games because those are the only type I get put into 75% of the time.
RftW continue to be garbage, except for the first mail each day you open per character containing transmute crystals. Post-match rewards are mostly garbage as well, except in very rare cases when you get a decently traited item for impreg or riposte. Anytime I get a decent trait it's attached to a helmet or shoulder piece. Thanks RNG.