* Improved migration format: make it possible to create new initial migrations as a project evolves by rebasing. Meaning there's no need to keep or execute the whole migration history every time. On my current project running migrations from starch takes 30mins :(

* Improvement in performance in regarding to JSON generation or other thing is always welcome. following benchmarks can be taken as reference where rails stands currently. Any improvement in the above stats would be awesome http://www.techempower.com/benchmarks/#section=data-r6