Nice post DT.
I agree that Tom gets a bad rap in a lot of respects.

But Sonny didn't have the freedom to lie low and play possum for two or three years.
He was in a hot war he didn't choose and the entire Corleone power was at stake.

He couldn't negotiate the Sollozzo deal (without Sollozzo) which is the least of what the other Families wanted.
He could not replace the consigliere or get new capos as Mike/Vito did.

His only choice was to surrender or come out swinging.

Mike and Vito were able to make their plans and lay low because as Boss, Vito had the power to unilaterally change the Corleone Family policy on drug trafficking. This brought them the critical time to train Michael, build secret regimes and expand/transfer political power. Sonny didn't have that kind of time.

Even though Sonny disagreed with the initial policy and was at least tangentially to blame for the ensuing war, there's no way Sonny would have gone against his father in a matter of business and told the other Families that he would now support drug trafficking, regardless of what Vito had said.

We can really ask the question of why didn't Vito order Sonny/Tom to give in and make the same plans with them as he later did with Michael. The story wouldn't have been as interesting of course.