I couldn't exactly predict how much exact time it would take for me to implement each and every feature. But,I have tried my maximum to optimally allocate time to these 5 tasks only, out of which some are big. And yes, I think I can do more tasks than this, but am short of ideas.

At present, I cannot come up with any new ideas regarding user interface improvements.

If possible, I just wanted to be advised professionally and out of your experience , is it possible to scale this 5 tasks to a duration of 12 weeks?

Also, can I add "solving bugs and feature requests from trackers" as a milestone and devote some time to it in between tasks in my proposal?