Please Help Me Upgrade My Old TDM Rig

[ProTooler]

I have an old ProTools system and it’s time for me to make the upgrade. I’m looking for some help from you guys who have been through this process. I’m way behind on what’s new, so please forgive my ignorance.

I want to be able to track live drums without latency, preferably with a lot of tracks already recorded with a bunch of plugins on these instruments, and with plugs also on the drums so the drummer hears some good drum sounds in his headphones. My current kit is using 14 mics. I’m not sure if this will be an issue with a PT native system or not. Would there be an advantage in going HDX in your opinion?

Having said all that, here’s my current system:

Mac cheese grater (Mid 2010 - 2.8 Ghz Quad Intel Xeon) OS 10.7.5 w/ 10GB RAM - *No Thunderbolt*
PT 10.3.8 HD TDM. I have 4 TDM Accel cards in a Magma expansion chassis.
C/24 control surface - Will this work? I can’t get a definitive answer from the Avid website.
Several TDM licenses

I’m going to need a new computer, interface(s) and expansion chassis (if I go with the Mac Mini).

My 3 old Digi interfaces won’t work with a new system, so I’m asking for your advice on what interfaces you guys think would give me the best bang for the buck. I think I can get by with 16 inputs. I can probably get by with 8 analog outputs. I have pretty good mic pres, so I don’t think my new interface would need mic pres.

As for computer, I’m reading that a lot of people are happy with the new Mac Mini. Is that what you’d suggest?

Thank you so much for taking the time reading this and for sharing your expertise.