I agree that a boating or kayak forum will yield better results. The only aspect of it that is bike-specific is storage capacity and how small it folds down. Those two factors are going to be important to more than just cyclists, so you still might find that info even if it's not in relation to bikes.

I have read a few blogs and trip reports involving packrafts and bikes. The main company that comes up is Alpacka. A number of their rafts seem suitable. It just becomes a trade off in which the bigger the raft, the easier it will be to attach all of your luggage and you bike, and the harder it will be to carry on your bike.

If you're not talking about whitewater rafting, I'm guessing a spraydeck would be entirely optional. The pictures I've seen of people packrafting with a bike attached usually do not have a spraydeck. It might even be that attaching your bike to the raft makes using a spraydeck difficult.

While I've been lusting after an Alpacka for years, I know that I have other projects and expenses that are going to make the price of a packraft hard to justify, especially since it's unclear how much use I'd get from it. So I have been looking seriously at this one: https://www.klymit.com/litewater-dinghy.html
Not really in the same league as Alpacka, from what I had read, but considering I mainly want to occasionally cross some calm water or float down a lazy river, it seems like it might do the trick. Or least give me an idea of how much I would use a packraft without making my piggy bank cry.