I'd take the bearish side on 1 year at 50:50. Is that too long a time-frame?

I don't know, I think there are enough people bullish enough to find that attractive.
You are not proposing anything very controversial or even interesting, yet sure, it is possible that some member might agree to take the other side (bullish side) of such a bet.
I already explained why I was not interested in my earlier response to Biodom, which relates to our distance from the 200-WMA, which is currently right about $50,200.
I already stated that I would be willing to bet that the BTC spot price won't go below 25% above the 200-WMA until after the end of 2025, which currently 25% above the 200-WMA is right about $63k.. but I also said that I would be willing to bet that the BTC spot price does not go below $75k, even though currently $75k is 50% above the 200-WMA.
Yeah, I didn't think _you_ would take it. You're bullish, but you know what bitcoin is capable of. Just throwing it out there. Besides, there are probably options on BitMex or prediction markets that let you take a position like this and possibly with better odds. I have no idea. I just put stuff out there and if people want to disregard it, it's fine.