That's a shame, there are some pretty good games out now. And I'm sorry to ruin Lyn for you. It's always awkward to hear people talking about how hot she is, though.
Gnome's H-Scene was a major disappointment. I don't quite know how else to say it without going into TMI territory.
Let's see here. First I'd reccomend going for a mythos theme. Persona 1 and 2 were based on the Lovecraftian Mythos, Persona 3 is based on Greek mythology, Persona 4 is based on Japanese mythology... you need some sort of unifying theme to link together the antagonists and perhaps maybe the players. I'd recomend either not having a wild card or having the player for it be really good. Make sure that they have to put in the effort to prove they're capable for it, because trust me, everyone is going to ask. I also strongly recomend doing research into the different Arcana, make sure you know what they all mean and such and ask for the players to make sure that their chosen arcanas match up to the characters. The worst of the lot to be misinterpreted are definitely Death and Devil. People get those wrong so many ways that it drives me up the wall. Talismans or personal items of value seems like a good idea for a summoning agent, though. I've seen a few methods used, but I think people are better off coming up with their own ways instead of copying the cards or evokers. I reccomend maybe trying to set out a basic plot skeleton to follow anyways, having some free roam is good, but you're going to want a plotted out structure to lead your players along anyways, or else nothing is gonna happen.
Also, blaaaaaaaghlblah vacations aren't supposed to be busy.