Villain is 10/5 after 20 hands, so I guess hes rather tight :-)
Should we barrel and bluff the river?

I just started with Poker Juice and tend to get carried away, if someone just wants to skip everything I wrote and just give his own thought on how to play the hand, that would still be helpful.

Preflop:

I give him 25% and exclude a 3bet range of 6%. Against that range I only have 42% EQ. If he raises a straight and calls with 2pair+ and 8out straight draws+, he folds 87%.

Flop:
If he calls with K8+ he folds only 37%, if he calls with A8+, that number jumps to 80%, any thoughts on that? My blocker only has a 1% effect on that, so it can only be that there is a huge jump in his preflop range, meaning there are few hands that have an A and an 8 but many more with a K and an 8? Anyhow, continuing and assuming he only calls A8+.

Turn:
On the turn I think he only continues with Q8+, 85+ if he has a flushdraw, and 97T with a flushdraw, and his wraps=he calls 35%.

River:
I have 20% EQ vs his range, making a check +0.89$

If I bet 3$ I expect to get called by Q9+ =26% of the time.

EV bluff: 0.26 * -3 + 0.74 * 4.45=2.5$

This looks almost to good to be true, so where might be the mistake?