I'm not saying Toon Boom isn't a good program since I use it as well, but I've worked with Flash also- while Toonboom is more intuitive with rigs I find, I don't really find it hard to classically animate with it- mind you, for small animations. PS: no I wasn't paid by TB to say all that stuff. Adobe has already abandoned developpement on the software appart from some webdesign functions. One last note : Flash isn't being improved for animation. the only reasons you would need a premium version of Toonboom would be either for complex cut-out rigs that flash can't do (like Wander over Yonder) or to use the built-in module for nodal compositing. A lot of studio think that they absolutely NEED the full version but don't realise that if Flash does what they need, the cheapest bersion of Toonboom already does more than that.

The idea that Toonboom is more expensive than Flash is bollocks : a perpetual license for Toonboom Harmony Essentials is 375$, basically half of a perpetual licence for Flash for a software that already does a lot more. Also, Ankama has ditched Flash for their animated projects now : their Dofus movie and the 3rd season of Wakfu are now made in TVPaint. I know a couple of people who worked on the series and the general consensus was that Flash was an absolute pain to work with : It's not optimized for todays animation pipeline, it corrupts files on a regular basis and it's just not comfortable to work with at all, whether you're working in cut-out animation or in frame by frame. Ankama used Flash because they already had most of their team trained to use it since their first game (Dofus) was entirely made in Flash.

Toon boom harmony perpetual license