Using Ruckus R510 unleashed access point for a church?

I have a lot of experience with standalone Cisco access points (non-Meraki). Does anyone on here have any insight on using a Ruckus R510 access point for a church network?

Our current Cisco solution does not have a quick, easy way to implement per-user bandwidth controls. We have a guest network, but the password is not though a captive portal, and it's a static password (WPA2-PSK). I'd like the user to have to agree to certain terms before connecting. We also have some deadzones, and I've heard that Ruckus has pretty good beamforming that can help provide coverage near the outer edges.

Ruckus also seems to have a way for users to request access to the guest network, and to receive their credentials via SMS or email, and to have their access time-limited.

Some questions:

1. What do you think of purchasing a used Ruckus access point from eBay?
2. Do you need an active support contract to receive software updates from Ruckus?
3. This church is 5200 square feet with a main first floor and a basement. Would just a single access point work for around 30 - 40 users? I'm trying to serve all clients off one access point to avoid roaming and the issues with multi-vendor support. Our Internet feed is 45 Mbps down and 5 Mbps up.
4. Does the Ruckus 510 unleashed have the ability for deep packet inspection to block filesharing protocols (specifically Bittorrent) without any additional hardware? On the Cisco, I'd block the well-known Bittorrent ports on the router, but people can just DHT (no fixed ports) to get around this.