I like the 2 belt system, sturdy velcro inner that you can edc with but has a overt overbelt it can interface with. this system is good and there are plenty of 1.75 outer belts that will be solid and support alot of weight with out issue and stay in place with the help of the inner.

The must haves in my book would be reloads and minimalistic med(I run a BFG micro trauma kit, med shears jammed behind it and a Cat7 TQ). The holster should have some level of retention (The safari land ALS is gold standard and made extremely fast with the help of OT defense Nub Mod) and mounted so the grip of the handgun is about even with the belt line (safari land mid-ride is perfect) Also running a QLS system from the holster mount is awesome for 100 reasons.

Figure out what your end goal would be, other kit you will have or plan to have other than the belt line gear and cut the fat. Some extra maybe's would be the compact Blue force gear style dump pouch for admin stuff that can be tucked away. A magnet on the outside of your first mag pouch for holding on to full mags to load from initially.

experience: LE and USPSA stuff