If you get a jacket BCD instead of a backplate/wing (I'm not pushing either way on this), I'd get a weight-integrated. You can wear a weight belt even if you've got one (and for some reason want to), but you have to wear a weight belt if you don't have one.
The key issue with masks is a good fit. This is one area where more expensive higher end models aren't necessarily better. If practical, dive with a mask before committing to buy it. Especially if you are a 'difficult seal' kind of guy (like me).
If you anticipate shore diving where it's rough & rocky (e.g.: Bonaire), skip the thin-soled 'booties' & get boots with a decent thick sole (I like SeaSoft Sunrays for tropical diving). Helps keep ragged iron shore pressure points from messing up your feet as you walk on it geared up. For similar reasons, get open-heel fins, not full foot.
For a dive computer, I prefer one that can download dives to a computer, which I where I do my real dive logging. And can see a graph showing how my dive went. If a console, air-integrated. A lot of people prefer wrist computers, and they are very convenient to glance at; air-integrated is nice (if you can download to your PC, then it records start & end pressures & likely calculates your SAC, so you hardly need to write down anything at the dive site), though wireless AI wrist units can be pricy.
If you opt for a dive knife, don't buy a stainless steel knife or it will rust (unless you are quite diligent about after-dive care). One of the H1 models from Spyderco (I use a Salt 1) or a titanium (not cheapie titanium coated!) knife should do fine. A small one that clips on your BCD is fine. A big honking whopper strapped to your leg unnecessary.
I prefer LED dive lights; reputedly durable, long-lasting bulbs that use little energy & don't run hot. Some halogen lights are so hot they're not to be used above water.
Richard.