Filler in and of itself isn't the problem and to reduce critisim to this feels a bit unfair. I think most of the individual episodes here were decent, but there is an overall lack of any foreward momentum or well defined character arcs for the main characters. My problem with the aforementioned 'filler' episodes is that they rely primarely on cameo appearances and nostalgia instead.
We don't go off on an episode where we really dive into the how and what of an individual Bad Batch member, but instead we have the "Cut Lawquane episode", "Bib Fortune episode", "Fennec Shand episode", "Rex episode" "Trace and Raffa episode" "Bane episode", "Hera Syndulla episodes" etc. Individually they are often a ton of fun, but all this Who's Who in Star Wars leaves the show (at best) unfocused. In the case of the Mandalorian, each cameo at least tied into Dinn's journey and moved it forward, but that is almost never the case here.
So I definitely don't want season 2 to be cut down with no filler at all. What I would like is for the filler to focus on character exploration like (for example) Echo dealing with or at least responding to the fall of Kamino. Instead almost every single cameo character gets more dialogue than Echo every single week and he doesn't get any type of character arc either. Tech barely does any better.
Avatar: The Last Airbender is a perfect example of this kind of show that does get this right. 95% of it is filler, but it adds more depth to the characters every single week. That is the kind of filler we didnt' get enough of here. As a result this season, and the show as a whole, never really have a distinct identity.