R grails are the main change for me. Used to be 2 R got you to lvl3, then 1 more gave you 67% chance of lvl4 so was worth the gamble (the series 1 to n of (2n)/(3^n) tends to 1.5, so getting from lvl 3 to lvl 4 used to cost on average 1.5 R fuel, and gave effectively 2 R in return, so was worth it unless very unlucky)

2 still get you to 3 skill, and 3 guarantee you skill level 4. Takes 2 more to get to level 5, so you don't gain or lose anything fuel-wise, and useful if you are levelling up those high levels and need a lot of materials to get there.

So, R grails massively improved (always use 3 to get those grails worth 80 points), SR are exactly the same (use 6 to get 140 points) and SSR are slightly nerfed, but as I don't burn SSR weapons that's fine by me.

Now it is time for me to move that 100 odd R-grails in my gift list into my weapon list and hit SLVL30 on a few more MLB weapons, now it's about 4 times faster.