Someone asked for more FFXI Beastmasters so...here's my input. I'm Blaise's wife IRL, for the record. I played BST extensively in FFXI.
I really like all of the ideas here (except for the ones where the pets change classes and the pet is reduced to level 1 after taming

). FFXI BST was fun, but it was so punishing. FFXIV has a real opportunity to make Tamer/Beastmaster into a solid class/job. It doesn't have to be torture to level, and it has some potential flexibility for solo and party battles.
I really like the idea of having the option to tame a pet and keep it, or make it a temporary pet. I could use my preferred pet, but then if I pick up aggro or need to crowd control, I could temporarily dismiss my pet and charm the extra monster. I could do this in FFXI and I was pretty fun to be able to make enemies fight each other. I hated recycling monster after monster and never having a permanent familiar, but it was nice to be able to manipulate the monsters around me somewhat for my own safety and the safety of my party.