my classic app which i did develop is a medium size app, around 6000 lines of code and Ive been trying the past 2 weeks to learn scenegraph and slowly rewrite ALL my code.
My impressions so far... pure brightscript was way simpler than scenegraph here you have to learn about threads, nodes, components, xml, brightscript and a whole lot more. Brightscript was simpler, the only advantage so far ive seen with scenegraph is in fact drawing stuff on screen is faster and animations, but just drawing because when you need to code what that drawing or animation needs to do you have to start writing a lot of brightscript anyway.
To make my post short scenegraph is not better, its harder, has its problems but apps look nicer with all the nodes...
Brightscript was limited and was hacky, i had to do a lot of workarounds pretty clever ones to make my app great, I expect the same from scenegraph, the problem is its just new, give it time, let the forums grow on info.