Can't give bugger all in the way advice without a rough clue what your budget is to be honest, where you live also comes in to play significantly as I'm not going to recommend a store called UK Tactical to somebody in, for example, Canada. I think asking people what looks better is rather inflatable-dartboard as well, you'd be much, much better off just going through loadout threads on different forums or just browsing SF pictures online if you want to figure out what 'looks best'. Because that way you'll get stuff that you actually like the aesthetics of yourself, rather than someone else's opinion.
Even without knowing your budget I can tell you for sure that all black just looks like an airsofter loadout, not any sort of super cool high-speed operator super special forces dude. If you like the look of it then that's cool go ahead, it is of course your money. Just be aware you'll not see elite police firearms units or SAS or SEALs or whatever running much in the way of black gear like it was the early 90s anymore. It's also demonstrably very poor camo in urban and woodland environments, so if you want something that's effective for milsim look at either grey or a popular woodland pattern. Obviously US Woodland, Multicam (including any of the 3 newly released variants), AOR1 and AOR2 are super popular amongst all the super cool guys right now. There's also the Kryptek and Pencott families to consider in terms of the 'latest and greatest' for camo options.
Helmets are, if anything, low speed if you take the literal definition, but if you want to be fashionable in the manner I think you do then an Ops-Core replica is what everybody and his gran is rocking right now.
Eye pro should very much be decided on a safety first basis, not what looks good. End of the day if you just run the dark lenses in any goggle and cover your lower face somehow it does the job of dehumanising your appearance, which is always a winner on social media.