if you decide for a bubbletip try to find someone lucky that has one that clones and get one of them and that way youll know feeding foods and lighting water parameters.
none of the host anemones are easy to keep especial in a smaller tank so if its your first nem id skip a host and go for a mini carpet or tulip to get more anemone husbandrary down and build experience.
but most clowns will host other critters, my favorite clown host are leather corals.
you should aim for a very minimum of 4wpg, 6wpg being better.
I think a BTA in a 16 gallon is pushing it. Some get over 12" across and in my opinion a 16g is too small I go with a small rock anemone or something that will stay small.