15 is plenty assuming you've built a proper raid army for each boss, although iirc some pals can be used for multiple bosses so its not like you have to have a unique set of 15 for every single one.
Whether I disagree with them or not at least dudes like Juvaris and Trickle are consistent with their beliefs. It's funny seeing you defend this blackwashed faggotry so ardently when the rest of your posts are you larping as a hardcore conservative.
We gets tons of movies to high-five and ass pat each other about each year whereas you will be lucky if you get to gloat like this again this decade, which is probably why you're milking it so hard.
Raise the pal per base cap in the server settings and stack your buildings. You don't have to go completely insane but doubling the cap to 30 and building a 7-8 high stack of breeding farms (and a couple stacked ranches) makes a lot of the shit you're complaining about much less of a headache.
He already told you everything you need to know. How Not to Summon a Demon Lord. Comedic pervy isekai and the pervy stuff is more played for laughs than just 'hey check out our fan service'