No offense to you personally, OP, but as a rule I wouldn't participate in a group buy run by someone brand new. Starting an interest check with < 20 posts was not the greatest way to introduce yourself. That said, putting up some useful tools for group buy automation would be a great way to build trust and establish a place in the community.
I'm not totally clear on what you're proposing, but here are my thoughts. I agree with what others have said here that the group buy subforum is where group buys should take place. The approach that makes the most sense to me is to provide tools for the GB organizer to easily manage orders. I have a pretty nice system of Python scripts that does just that. However sharing them with other group buy organizers isn't simple since they are very kludgy and dependent on third-party libraries. I've been working on cleaning them up and generalizing them, but if you could put up something usable by non-programmers, without a lot of configuration, that would be fantastic.
Most user-facing things like deadlines, pricing information, and order summaries can and should be handled by a well-organized order thread OP. I don't think we need anything special there. I suppose the argument could be made that not everyone wants their order listed publicly, but that's what I've done for my group buys and no one has complained so far. For my
moogle group buy I wrote a script that scrapes my spreadsheet and updates the second post of of the order thread. I ran this script several times a day while orders were being taken, and that made it easy for everyone to see how the buy was progressing.
The biggest manual process in my current group buy workflow is changing people's orders. Google forms will allow you to update your order, but only if you have a Google account and are logged in at the time you placed your initial order. Sending out mass PMs (e.g., invoices) is also a pain, though I've streamlined it to the point of a few copy/paste operations per order.