I always start with jetting the way that Holley built them then see what the combo wants for the fine-tuning. Holley typically built them pretty close to how much fuel is needed for how much air they will pass

Any of the piston manufacturing people will make what you want, you just have to tell them what you want
Size,dome or dish, how big, pin size and length ring package that you want to run etc.

I was always told that the higher temp thermostats and running temps were for emissions reasons and an effort to increase gas mileage. The automakers did start using them it the mid 70's when all of the emissions stuff started getting crazy.
For me, the old stuff gets 160°, newer whatever lets the computer think that it's warmed up

Torque the mains back up without the seal and see if the crank turns ok. If its fine then maybe try a two piece seal just to see, there cheap enough to try.

Did it many years ago with a stock 428 cj cam, ran really well for many years
But I'm sure that does fall into that slow ramp category

I've got the M/T drag radials on the mustang and can say that they work very well on the street, just don't expect a lot of mileage out of them as they are very soft

Found ya one if you still need it PM sent