@SCH thank you, that is great information to have. The stake increase would have to be retroactive if the goal is reduce the number of nodes. I would think that once the parameter value is altered, any nodes that fall below would just be force unstaked, just like you would now with a node that falls below 15,000 min stake.
I know this is preliminary discussion, but I had a thought while mowing grass. If the DAO decides to go with the weighted stake option, it would be an excellent opportunity to introduce some weighting for quality, and trigger a quality arms race amongst node runners. A “quality” rating would be calculated per node, and an average per network per month. If a node runner consistently serves requests 10%,20%,30% below network average, that feeds into the formula and their probability of being selected for a session increases. This quality rating could be as simple as average response time. If the weight assigned to the quality portion is sufficient, you could see node runners begin to invest in higher quality hardware instead of higher stake amounts, which would be just as valuable. Also, not investing in keeping up with at least the average network quality could leave your node less likely to be selected for a session, and therefor less profitable.