Try as I might I cannot find a benefit to this new launcher. It uses more CPU, and adds complexity. Could you possibly continue the development of the stand alone client as a pay for app?
Did you read previous messages in the thread? E.g.
- WatchFul11's comments about backend and tools: https://forum.feed-the-beast.com/threads/ftb-launcher-news.158980/page-10#post-1696497
- My rant about FTB Launcher's code: https://forum.feed-the-beast.com/threads/ftb-launcher-news.158980/page-12#post-1699266
- Quetzi's comment about FTB Launcher improvements: https://forum.feed-the-beast.com/threads/ftb-launcher-news.158980/page-14#post-1708316
- My rants for previous "I hope development continues": https://forum.feed-the-beast.com/threads/ftb-launcher-news.158980/page-12#post-1699201 and https://forum.feed-the-beast.com/threads/ftb-launcher-news.158980/page-8#post-1692614
FTB Launcer is not standalone application. There is backend for packfiles and application for pack submissions.