All these measures won't stop bot users just because of one reason:
Bot users can calculate with the AVERAGE claim amount, because for example if a bot user has 1000 accounts that claim 24/7, he will roll a 10000 almost every day - It's pure statistics. Therefore the amount bot users will calculate with is the AVERAGE claim amount, not the MINIMUM. The AVERAGE claim amount is currently around 172 satoshi. Before you halfed the MINIMUM reward it was like 10 satoshi higher, so not significaltly different. All this does only apply to users with lots of accounts, cause they will hit the high rewards in reasonable time. Regular users will need multiple years because of the low chances.
I wouldn't be so sure. If each roll is an independent event (and very likely this is the case), the chance to get a 10.000 is always the same regardless of the number of rolls you make. And it is equal to the chance to get every other number.
In my opinion is also wrong your assumed average: you can easily roll 10.000 getting always the min amount. Then, if you want to support your theory and you want to come to the average you say by including in the sample rolls paid more than the min (but having the same chance to happen of all the others) you are simply choosing an arbitrary interval and produced a biased result.
All of this if each event (=roll) is set as an independent one. If you evidence that is not so, please let me know