How do you decide what your next upgrade will be?

Having a Nighthawk makes this easy. Call Dave Thompson, chat him up about what tubes he recommends. The guy is some kind of tube genius. 

As far as system upgrades, the key is to understand it is in fact a system. Things such as the springs a component is on, the wires that connect them together and the room they are all in are every bit as important as the components themselves.

This is a hard one to get. A lot of audiophiles still don't get it. Put your Nighthawk on Nobsound springs, or even better Townshend Pods, I bet you get it then. Put a QSA Violet or SR Purple fuse in it. 

Then you will see. By the time you have done this a few times you will have learned so much by experience you won't even need to come asking what to do next. Congratulations in advance.

STONES. Don't forget those 

Marvelous QSA stones! :-)))

Funds dependent.

Depends on availability as well, living in a remote 240v country.

I have a list of things I want to purchase.

Slowly progress on these.

i.e. A modded HiFi router is on it.

Although when looking at big changes?

Dac first, then speakers, then power cables, then interconnects.

It came down to what changes woud make the most improvements to my system.

Instead of thinking about upgrading equipment, think in terms of how to improve what you already have. Think in terms of room treatments, reducing micro-vibrations, and cleaning up your AC power. Done right, these things will get you off of the equipment merry-go-round.

Frank