Do you have a website? I would love to follow your project closely. I do understand you're still on an early stage, but even so I would like to know about progress and so on. Also have you tried announcing your project on the English Amiga Boards
? There are plenty of people there (like Kroah himself) who dedicate themselves to reverse engineer classic amiga games. JOTD is a good example, he fully reverse engineered Gods all by himself and is currently working on a Cadaver remake. It would be a good idea to contact him to get some feedback, as he is not only a huge Bitmap Bros fan, he's also an amazing programmer and a very nice person, who will certainly be able to give you a few valluable tips.
As for the online multiplayer, I would reccommend you to at least consider it. Chaos Engine was insanely fun in coop mode. In fact if you check youtube for let's plays you'll find out most Chaos Engine LPs are two-player collabs via emulator. The fact that you are also planning to create a map editor is a complimentary to this, as it would lead players to actively create and share maps to play online.
Also, have you checked this
thread? Perhaps you should try contacting this guy in hopes of joining forces.