Many thanks for your replies and pointers; I was away camping and mulling these things in my head. It’s the times away from my music room that I tend to think about amending it to be honest.
Anyway . . .
I wanted the 4 sends for the 4 effects devices that I use; on the Mackie I only had 2 sends and this was sometimes restrictive.
I also wanted to be able to take a number of the individual outs from my DRM Mkiii and process them. I also needed 4 stereo ins - 2 x OTs; 1 x DN; and one pair for the remaing stereo outs from the DRM.
USB wise, I wanted to get Ableton sounds into the OTs for sampling and also have the ability to use the external effects on some sounds from Ableton.
While considering all this in a tent in Germany, an Alto 1604 appeared on eBay for a good price so I hit the purchase button.
It’s currently working really well. Having to rethink things a little to create a foundation that works. As with every change, there is a settling period where you realise possibilities and restrictions. I’m currently finding my way.
The mixer looks and feels and performs well. The audio from Ableton is only 16 bit but is relatively quick.
However, am already thinking how individual outs from Ableton would be great with quicker and higher quality audio. Noww that would be another lump of money!