Is there a way to force tixati to only connect to certain seeders/peers, and ignore all other seeders/peers?

Additionally, is there a way to set maximum peer connections to a number below 25?

I think you could do this with the IP Filter. Make a list of IP's you'd like to connect according to proper format. Make two rules: 1) Accept Matches for Incoming and Outgoing Connections from the list 2) Drop Non-Matches for Incoming and Outgoing Connections from the list.
25 peer connections is minimum.

good idea thanks.

Actually I think only the 2) rule is required, most likely the 1) wouldn't do any difference.