So, for a pool, I think what you would do is just have people send the BTC equivalent of one block's reward to the pool (which isn't much), then if the miner's steal the reward, the pool still retains their deposit so net miner gain is 0. You would have the miners themselves mine to their own pubkeyhashes, and you'd submit partial solutions to these blocks to the pool itself. When the miner gets a block, they would be given n many blocks to get the coinbase from their block to the pool to redistribute to the other miners. If they didn't return the reward to the pool, the pool would then just take their deposit and ban them.
So, I don't think there's a big issue with pooling, just a slightly more complicated implementation. There's a small associated cost with joining a pool, but it's not really much.
coinbase mature is 120 blocks, pool have to wait that time, before spend the block reward. a big miner can mine more blocks during this time, so every miner sould pay a bigger guarantee (60 spr for 10 blocks, 120spr for 20 block guarantee), do you think they will do this?
Probably, yeah. Considering 100 SPR is only $6 USD and assuming that that majority of miners probably have a cheeseburger worth of funds to spare, it should be fine.
I mean, reward is like 6.66 SPR, *= 120 blocks (worst case, extremely unlikely) is ~800 SPR. But if you have enough to get 100% of the network's blocks, why would you be on a pool? More likely case is that a big miner gets maybe 20% of the network... That's a deposit of ~160 SPR to prevent a large loss.
This does discourage pools though, particularly if a coin gets more valuable. One could also have the mature time be longer.
The pool could also stop accepting work when x number of blocks in the last 120 have been solved by the same miner (matching collateral), but that would suck from the miner perspective.
In the event a miner started stealing coins, it'd be kinda a funny battle between the miner and pool to get the spending TX in the 121st block before each other for all of the remaining blocks (you would assume the pool would ban the miner at the first block stolen).
Though it seems to me that the pool should be spending the TX in the first block it's allowed regardless, so the miner wouldn't have 100% chance of even stealing the first block (pool possibly has a better connection as well).
