[nnq]

Cut the crap, if you're app is really successful you're gonna end up re-writing the UI at least three times, trust me, and you're probably also have to maintain different multiple UIs (think Android native, iOS native, web etc.)...

No biggie if one of them is opengl based and might be expensive to add accessibility to it...

Oh, and stop spreading fud in general, you might use an accessibility-friendly toolkit and still end up with a practically unusable for visually impaired ppl UI, just as you can make a custom coded UI screen reader friendly...

Just be honest, accept that UI dev will eat up at least 50% of your resources if you wanna do it right, don't cheap out on it, embrace re-writes and maintaining multiple versions of similar functionality things, and stop being afraid of new tech...