General configuration question from a noob

Hello all,
I have my untangle server set up in bridge mode. I have both wireless and wired clients. I would like to set it up like this:

Cable Modem ---> Untangle Server Bridged ---> Asus Wireless 4 port Router ---> Dell 24 port managed switch.

The UTM appears to work just fine in this configuration but I was wondering if there are downsides and or vulnerabilities/outside threats in the setup?

Any help would be greatly appreciated

Thank you,
Rich