Then you got plenty of options where you can go if you are not happy with Stencyl

Though i must remind, that many of most successful iOS games are currently made with engines lot more expensive than Stencyl.. For example BuildBox which was used for Color Switch costs five times more than Stencyl.. Construct 2 is cheaper if you only made games that won't make any money.. Personally i think that 199 dollars is fairly cheap for whole package and i'm also very willing to pay it in future if Stencyl can keep up with the openFL developing cycle..
For you Vertex better option would be to just use plain OpenFL and Haxe for you game development, it's free so you don't need to wonder about paying.. I personally see that Jon/Stencyl got every right to make us pay for this nice tool..