New Wireless Network Install Advice

My church is building a new building that sits about 2500 people.
I’m over the network wireless and firewall project.
I’ve used Mikrotik in some small jobs for Wireless AP’s and Firewall.
I will be using Mikrotik for the churches Staff wireless, Public Hotspot and firewall needs.

Questions

Should I use one SSID for the Staff laptop wireless so they can roam or Different SSID for each AP to make them choose the best signal?

What board, radio and antenna would you use?

Is there some do and don’t you have learned about doing a project similar to this one.

Thanks
Darrell