Is getting most of my swaps from here going to put me into a kind of "bubble" where my connections aren't very diverse?

When I use this service I try to connect with nodes that have few if any channels with me. I just keep checking the site for desirable channels. For example, I check their fees, channels, channels sizes, channels in common and if they look like they could be a good peer.  Hope this helps. Cheers

I think not. Also, new users are coming every day.