Keep in mind this. It's your decision and you live with the results. Nobody has the same story on how they got started, where they are now or where they're headed.
You will have your story as well and your own unique set of experiences from the journey.
At times that gets lost in the db blabber which we love to engage in, myself included. For me, like the next guy I have my preferences of equipment and how the systems are laid out architecture wise.
At your point, with the questions you are asking let me also suggest this. Coming here and posting the thread is great. I don't know what your experience is with the world of mobile DJ equipment. Back when I was getting started I was like a sponge. Went out to many many clubs and carefully looked at their systems, how they sounded and the installation itself, brands, etc. Also the lighting. And checked out lots of clubs with bands playing, band/DJ clubs. And went to any event I heard of with a mobile DJ playing, even the local FM radio live DJ appearances.
If you can go out and see what the other guys are using and how well it works for them or how bad it sucks. Look at everything. Subs on floor, tops on stage or platforms, ground stacks, do they use monitors or just headphones. Wired or wireless mics. Mixer layout. Most of the guys I've know since the 80's that are still playing have a DJ mixer or controller that feeds into a regular audio mixing console. The main console controls all the mic inputs and has line inputs from CD players & laptop for dinner music and such.
That's how my stuff is setup as well. Wired mic for the DJ, also a wireless for the DJ & a second wireless for the guests to propose toasts and such - system is optimized for wedding receptions. Also has monitors that sit on the DJ desk on a high pass filter at 120hz as there's plenty of LF from the mains for the monitors. Are you going to work alone on stage. I use the lighting guy to assist the DJ with iPad mixer control of the mics when the DJ is out front for MC duty and making introductions.
The system mixer in my setup is an Midas MR12 and works great. It offers TONS of processing options you want that a DJ mixer or controller doesn't have. Compressors and limiting functions for the overall system which can be preset to sound levels and help the DJ manage it overall. Having compression/limiting also on the mics, especially the guest mic so when it gets dropped or some idiot trys to get cute and scream into it is also something that's really necessary for a professional level setup.