It's player dependent. BvB people will hero call you a lot more often but here BB has a capped range once there's no raise on the flop or turn. I don't think it can really be bad, but I guess at 5NL you will see 54 and 98 slowplayed a lot more. you should be able to get him to fold quite a few combos such as 87, A6s etc

In the micros I think you will have more success 3 barreling with high card boards when your range is uncapped and villain has a lot of second/third pair which will auto call 2 but fold on the river.

2 shots here look good. The problem with the 3rd barrel is the 2 changes nothing and quite a few draws bricked. If the river was a 2d I'd like betting more.

I don't expect 7x or better to fold here, perhaps even 6x depending on the reg as it's BvB.

Since this is bvb I think his range can be a lot wider and some stats would really help here.

For example, some players might have just about every 7x that's 75 or better so your range estimate should include stuff like K7 Q7 J7 T7 all the way down. Also I wouldn't include something like JJ in his range since most players will 3bet that preflop and might be doing it with stuff like 88 and 99 as well.

I do agree that villain should have raised many of his strong hands before the river so his range should be relatively capped.

On this river you're probably getting called a lot since the world missed. I definitely think there's a good chance you'll be called with 7 or better. That being said, you don't want to be 100% for value here so you can bluff sometimes and this hand seems like a good candidate to do it. K8 blocks some 7x hands, bluffs 88 and the nut straight and does not block any of the flopped flush draws. Bluffing this hand should have a higher success rate than bluffing many other hands.

I would bluff this hand but if you get to the river with, for example, any diamond draw, any club draw, any 8x, any 9x, any 5x, any 4x suddenly you're bluffing WAYYYYYY too much so you need to give up with a lot of them.

Thanks for responses guys! Much appreciated