Choosing the right routerboard...

Hello to everyone…

I want to make a hotspot on the hotel of a friend.
He has a unifi outdoor for access point and a RB751U for router.
The max people that will be ever connected are 20-25.
The things i want from the router are 1.equal bandwidth management and 2.one user not to be seen by other users.
Do you think the RB751U is ok for all those? Or do i need to get a new routerboard?The most important is the wifi to work perfect, so we can buy a new one if its nessecary.
Also, i already set up a hotspot with unifi outdoor.Is it better to make the hotspot in the routerboard or should i keep the unifi hotspot?Or even possible to buy a mikrotik outdoor access point?

Thank you very much

The RB751U has a 400MHz CPU, the RB951G has a 600Mhz CPU. Depending on the number of rules one will work quicker than the other.

Someone told me about 450G.
For my case(20-25 guests,equal bandwidth management,not to see one each other, maybe hotspot manage), which is the best?