what do I upgrade?

I agree with the posts above, dedicated circuits and power conditioning, including room acoustics. I would add high quality AC outlets such as the cryo'd Porterports sold here on Audiogon (one of my favorites).
Secondly, if you changed your interconnects you most probably will hear a big difference in what you stated you wish to improve. I have been most impressed by the interconnects and speaker cables made by Ridge Street Audio. They work very well in my tube and SS systems.

Dedicated circuits: if you had done this to begin with your upgrades would have been more enjoyable along the way, AND PROBABLY NOT HAVE SPENT SO MUCH - BASICS FIRST!!

I spoke with several electrician and don't think dedicated circuits will help since I live in brand new home in a newly developed area. Is this true? Also, what power conditioner should I be looking into?

Allen, as a general rule electricians are not electrical engineers and therefore, no not what they speak when it comes to benefits of electrical tweaks.

Everybody has dirty AC and therefore everybody can benefit from properly treated AC, every digital source injects noise back into the wall for other components to pick up, and most any amp requiring a decent amount of current draw will benefit from a dedicated ciruit/line even at lower listening volume levels.

The only advice I would suggest following from your electrician is when it comes to safety as some to many do know about that.

-IMO

If this is my setup, I would
look into high current Jeff Rowland amps.
The Wilson speakers do suck a lot of juice.
Definitely a super size power cord will help too.
I would get a nice tube preamp.