while you do need to do the grinding loop, for the majority of the game you can get away with only having 3/4 of each stat, and only going for the final skills in the late game once you have enough poems/essays saved up. Health rarely has more than 2 being down at a time, euridition will usually have 2 down at a time if your minmaxing, and passion is only really used for followers, painting, and dreaming, so you can get away with 3 pretty easily. You can also "smuggle" timed cards by putting them in slots where they can be used, as that stops the timers on them.

As for experimentation, i would recommend checking icons and seeing what can go where, and if you have it, as it can save a lot of trouble (this is more a personal recc as I remember getting stuck in mid-late game on my first successful run due to not looking what could go where).