Running rich at idle is usually the float is too high. Adjust the float level until it barely come out the sight hole on the right side of the bowl. If you do not have the instruction be sure to download the instruction from the web site.
Power valve is just fine like it is. It only open when the vacuum drop to 5" of vacuum, it is for fuel enrichment during full throttle operation. Changing it to a higher number will not help your acceleration, it could make your engine run worst by making it run too rich too soon.
If you have acceleration issue will need to make changes on your discharge nozzle (stock is a 28). When you snap open the throttle and it backfire through the carb you need a larger nozzle, I would go to a 35 and see if the would help. If it bog down then accelerate OK the you need to go to a smaller nozzle, maybe a 24. You can go up or down from there to get the best response. There is a couple of other adjustments that can help fine tune it if needed. Here a link for some of the different sizes:
https://www.summitracing.com/search/...charge-nozzles
Also I would stay with the same style of nozzle.
Once the above is working right the recheck the idle speed and idle mixture.
Keep us posted on the progress good or bad so we can get the engine running great.