One thing that I also saw as useful (which i initially didnt think) were the "1/x x being the current hp" (or something) blocks.
In one run I about got this as the first block, so I let the enemies hit that I only had like 1/10 hp left .which was a nice block to use for cooldowns.
but that aside, grinding together 2 or 3 times eaach variable block, some "nothing" blocks and such sure takes a while