Hand me down audio equip- upgrade advice


First off, this might be my first post, but I’ve been admiring the Audiogon community for a while now. There’s a ton of helpful information that a lot of you have shared, and I appreciate that!

I’m lucky enough to have a boss who’s big into audio equipment, and handed down some of his older gear to me:

Benchmark DAC2 D
Classe CP-700
NuForce Reference 18 monoblocks
KEF 103/3 Reference w/ Kef Kube equalizer
Vandersteen v2w sub

I ended up having to refoam the KEF’s, but I have to say they are a great speaker! I’ve been enjoying this setup for about a year now, and want to explore some newer speaker options- preferably a floor standing full range variety. At this point, I’m fairly overwhelmed with the options out there- and looking for some wisdom.

I’d like to keep my first upgrade under $1500, with some wiggle room. I’ve been drooling over some Sonus Faber’s, but alas, I’m not ready to bite the bullet on anything in that price range (used, of course). KEF has plenty of lower to medium priced speakers, but I’d like to explore other avenues.

Thanks in advance
rillerr
Wow, what a generous and significant gift! Straight up, with resale value and $1500 put in you are not assured a significantly higher performance from swapping.  A demo comparison would be important.  

You didn't mention cables. If you do not have aftermarket ones, 1500 in cables for entire system would be appropriate and efficacious.  
I have no interest in debating my recommendations.   :)
HI,
Power distribution is as important if you have already solved the signal cabling. If happy with your speakers now why change?
Thank you for your input. Yes, a very generous gift, indeed. I have foundation 
research cables and conditioners for everything- I’ll be updating outlets in the future. I also have good quality cabling for each component- so at this point I’d like to dabble with some different speakers. I don’t intend to get rid of anything from my current setup at this time, just don’t know how much I’m missing out on without trying something more robust. 
I plan on going to some listening rooms, but unfortunately they aren’t in abundance where I live. 
Try and hear a recent iteration of the Vandersteen 2--a used model should fall in your price range.