It seems everyone is never totally happy with their development tools. Be they off-the-shelf (e.g., Lectora, Storyline, et al) or custom. Off-the-shelf is expensive and custom is worrying.
There’s a project afoot to create an open source elearning development tool: Adapt. The focus is to create a tool that’s better at building courses/interactions that play nice on all sorts of devices (hence “adapt”). However, they also want the tool to be robust from traditional learning design and development perspectives.
Open-source has been successful in many domains, no reason it can’t be here (just don’t tell Adobe, Articulate, et al). I know that we at NIIT Cognitive Arts would prefer that differentiation be a question of design sense, not tool or tool capabilities.