Guaranteed deployment, and the lack of an IDE which works for both programmers and artists were definitely the two advantages Flash had.

I'd really like to find a replacement which clicks for me the way it did --- started out w/ its predecessor, Futurewave Smartsketch (used it on PenPoint, Mac and Windows, and for Windows, continued using through a succession of pen tablets, most notably my Fujitsu Stylistic ST-4110 which I despair of replacing --- transflective displays went out of vogue).