Kudos to the op for such a well thought out design and effort into your idea. Unfortunately, there is alot of anti-ffxi sentiments on these forums from what I've noticed. Probably WOW players that tried ffxi and didn't like it.

I think pup would be a great addition to the pet classes in this game and the overheat mechanic/UI bar you created is neat but if a pet stops attacking completely that is a severe dps loss. If anything overheating would limit a puppet to auto attacks only for a certain duration and then the heat % deterioration can resume. Pup could use some different ability/skills reworking in regards to its ffxi counterpart though so that it doesn't seem so similar to monk in playstyle. We don't want the same problem that scholar and summoner had/still have. I'm sure the dev team will think of something when and if they do bring pup into the game.