First of all, thank you for all the new exciting and useful nodes! There are some I really wanted.
However, your loop ends are missing the (also new) Allow variable column types option of the base nodes. Any chance to get something like that? (Use case: rows producing missing values followed by rows with actual values)
And just because I'm already at it: especially with up to six different tables, only being able to set Add iteration column and Uniquify row IDs for all or none of the outputs is a bit limiting, although easy to work around.