I've changed BMX style one piece and MTB sq tapers in the past but never done anything with newer crank systems.

I have a Deore crank on My SPesh Pitch Pro.  I want to take it off and replace it with the SLX I have sitting here, purely because it looks nicer.  What tools do I need?

 Also, again, sitting here (for a three years actually) is a set of Blackspire rings.  44-34-24

Would changing the standard old 22 and 32 with a 24 and 34 respectively cause me any issues with chainsuck etc?

To change the cranks a 5mm allen key and the tool for the end cap (though a 1/2 chisel will fit). If you change the bearings too then the proper cup tool.

24/34 won't be a problem but 34/44 will mean setting the mech about 5mm too high in relation to the big rig to prevent it fouling the middle ring. Edit: a 46 big ring is best with 24/34