Upgrade path

@OP. You are a long way from getting to a point of small incremental improvements. 

However, as this is your first real hi fi system, you should spend time listening to it.

At the same time, the best investment you can make is to go listen to as much unamplified live music as you can - when I say unamplified, I mean non classical/folk/jazz some of which may have small amounts of sound reinforcement, but not big PAs.

Then setup and acoustic treatment of the room before you change any of the equipment.

Then if you are changing any of the equipment, including cables, make one change at a time and listen for at least a couple of weeks to be sure that what you are hearing is an improvement and not just a change. 

Try to find a dealer with knowledge and integrity - it will save you money in the long run. BTW, while Naim equipment is not my particular cup of tea, as they would say in Wiltshire - I think what you ended up with is a pretty well balanced system.

Is this just a dedicated space or a full room ? If it’s just a space build a room if possible 

It’s a room (basement) that also has the biggest tv in the house. It’s shared space, so I’m somewhat constrained in the amount of tinkering I can do with the space. But some amount of room treatment is possible - thanks for all the suggestions along those lines. 
 

@rskey it's not surprising a post like this resulted in so many suggestions/opinions going off in so many different directions.  The fact of the matter is that you could do many, many things, depending upon what you ultimately hope to achieve.  So, I'll cut to the chase.  In a room of those dimensions, 40 watts of amp power is just not going to cut it if your aim is to fill it with concert or performance level sound.  That being said, keep in mind that one upgrade leads to another and then another and then another etc. 

It's also possible you will like the Totems more than the ProAcs