Well, if you can get some "inside information" from the hosts, it can't do any harm, but I don't think I've ever been to a Burns supper here in Scotland which wasn't treated as a formal, dinner suit equivalent type of affair.

So personally I'd definitely have the black bow tie option, and pretty much as smart as you can go with the rest of your choices.

My best kilt is the black, but the red one is only a smidge less nice, so maybe I could wear the non-tartan reddish kilt to avoid being too black?
If I was wearing black hose - which I would be - I'd go with that idea!