Good to see she is back, I know what that Itch is like to get back to something.
But, I think first thing she should do is review her available time to commit to modding, just to ensure she doesn't bite off more than she can chew. More for her own sanity than anything else.
After that, perhaps talk with the various modders that have replicated most of what RP2 has done, give advice/knowledge/support. Would make more sense to help improve/evolve what has been done in her absence, instead of starting afresh updating/redevloping what is already out there. Would rather see Elo's skills put to new shiny toys, but saying that, I would love to see her tubes (err, that just sounds wrong...) back. Sure we have ducts and mekanism that do virtually the same thing, I just find ducts too "easy" what with a cheap servo giving a massive amount of functionality within the same block. Meks system is more "text" based then gui, so you can end up with a awkward long list to scroll through, compared to say the Sorting Machine.
On the subject of ducts and multi-part, do whatever is required TeamCoFH. The only real reason for the FMP support is to stop pipes joining, although most people wanted that support so they could just hide their pipes. Bah, if you are playing with tech, you should see all your cables/pipes everywhere, not hidden away to make things "pretty".
You could use the system used by other mods where you paint the ducts, and only ducts not painted/of the same colour connect.