Let's create a structured spellbook, preferably with levels, so that a level 1 character, for example, wouldn't summon a phoenix (agree, that would be funny).
As for the parameters (strength, agility, etc.), we should keep what's in the rules (if I'm not mistaken, there are 5 of them), but if there are more, I'll definitely get confused. In general, 4 standard characteristics are the most optimal option, familiar to all players, and it's immediately clear which parameter is responsible for what.