I've had several different sets on my Glock 23's. So far my favorite are my Trijicon HD Night Sights. I've been running them the last several months and love how the back sights are "blacked out" and how quickly front sight acquisition is. I also love how awesome the rear sights are for one handed manipulations. They are pricey but they are arguably some of the best handgun sights on the market right now IMHO.
I also recently bought a new G23 and am not unhappy at all with the stock sights. My G22 does have Glock night sights but for most of my shooting the standard ones on the new G23 have been just fine. I'm in no hurry to make any changes at this time. Since you sound happy you might just want to stay put until something comes along that you like enough to make the change.
The biggest issue with assembling an AR isn't so much getting the parts together right - it's getting the right parts together. You'll remember the quality of a gun long after you forget how much you paid for it.
US Army 1966-69, VFW Life Member, Retired Geek