You can have rear ported speakers close to a wall if you're going to cross them out before the port moves much air. I suggest finding the tweeter that sounds right for you. That is the most important part for me also, hate harsh highs.
One thing, you reduce harshness by treating the bare parts of your listening room with Acoustic traps. Might help if you found a speaker thats perfect but doesn't sound good at home.
I'm awaiting your auditioning results before I recommend anything else. Anyone can pimp what they own.
SheepStar