It depends somewhat on this TODO:
check if above makes sense - gajim might intelligently set a Tor socks user name per account already and manually setting a user name might worsen that
Depends on what upstream answers. Does Gajim set the socks user name different per account? If it does, torsocks might kill the DNS leak, but would also kill the per account socks user name isolation.
torsocks can only be a solution, if it's known that the application is known to play well with torsocks, i.e. long term tested, mentioned in TorifyHOWTO, audited by somene. This is not the case with gajim.
uwt is just automating torsocks. Cannot surpass torsocks in terms of leak prevention. The first question to ask isn't uwt, but torsocks.
bindp is only useful for applications using incoming Tor hidden services, that are opening local listeners on localhost 127.0.0.1 that should rather listen on eth0.