If you're happy with the quality of low-motion scenes at a given crf but you want high-motion scenes to get more bits, then yeah, just raise qcomp instead of lowering crf. Good qcomp values are mostly in the range of 0.6 through 0.8.
But before that, I'd stop using tune animation and deblock 3:3. The low aq-strength and psy-rd values that it sets, along with the strong deblocking, are probably the main reason the rain is getting smeared even at such a low crf.
For most anime, I leave deblocking and aq-strength on the defaults (except when using aq-mode 3, in which case 0.8 is comparable to aq-mode 1 at 1.0), and psy-rd 0.8:0.05 (or 0.8:0.1 for 8-bit encoding) works well for most sources.