"If I am leading some middle flushes it does mean that I can lead here some of the time with blockers to these middle flushes also." Not sure about this. If they have big flush or full house I dont think they care about you representing middle flush In general when you are using blockers then use only nut blockers (if we are talking about multiway pots).

Here I agree with you that we might lead out small to get called by 6 or maybe even crying call from ATxx, AKxx with K of spades.

Its really hard for them to have a lower flush when you have Js 9s and the Ts is on the board. With the taken line from everyone i dont see them having any 6x. So here you basically need to get called by Ax to get any value.

Your "blocker bluffs" is way to strong hands that I much rather have in my cc range here. When having a 6 you have great SD value and bluffing these and vb j9ss doesnt make much sence.

I will take a 1 stab here at the river when we have hands thats worse than Ax. Since you can still have some 6x i guess checking twice to get someone to protect their A and also some high flushes.

Vb range for me is Qsxs (thats not Js 9s)+ mixing in some random hands that has Ks or Qs as bluffs.

Then we can have some 6x and medium flushes in check range so we can protect that. Some of the time going c/r with 6x and A6.