We will not stop releasing updates entirely while we finish up big features. We did that when we were rewriting Blesta for v3.0, and it was a mistake. We need to be consistent with releases, and there are tasks big and small. Filtering was pretty simple, and it's useful for the majority.
Everyone has this "one feature" that they need, and all other features are "useless" to them. That's the wrong way of looking at it. New features that you may not care for, someone else cares for greatly. We can consistently release updates with new features, while still working on the big ones.
Affiliate system excludes tax in the payout amount, it looks at the package price pre-tax. So if your payout rate is 10%, and the item costs $100 + $30 tax ($130 total), the payout would be $10, not $13.
You referenced quite a few potential new features, if you don't mind, please check that they are individually listed at https://requests.blesta.com with sufficient detail. When we plan new releases, we review the requests site.