Yeah, it's slim pickings at the moment as no matter how high pedigree a manager you bring into the PL, quite frankly the PL may just turn them upside down anyway.
Could always bring in Claudio Ranieri. Maybe he can bring Vardy along.
In all seriousness, I wouldn't know where to look for a manager right now. I just get the feeling it's more about finding the right manager for the club rather than grabbing a random high grade manager and running with them. Guardiola has never picked up a struggling side, Mourinho doesn't play aggressive football, Simeone is an unknown at the top outside of Athletico (although his achievements there are solid), and I'm not really sure I want one of the older managers right now that are just doing a few things before they retire. So yeah... slim pickings.
I don't completely mind LVG but he doesn't really hype you up in any way. I dare say even Moyes played us in a more attacking way, although often that ended up being the problem because he would too often rely on big name attacking players and just swamp them onto the pitch with no regard for defence.