First off, that's not nearly enough value to get Doughty. Secondly, you don't need to trade for Tavares' rights since he's a UFA, but if you wanted to. that trade wouldn't make any sense since Bozak and JVR are also UFAs

Yeah, LA would want Marner oe Nylander as the centre piece of a deal coming back.

One would almost have to be included to:

a) get LA to make the deal; and
b) fit everyone under the cap. Can't sign our 3 RFA's + give $10m+ deals to JT and Doughty

Yeah, just seems a bit hard too hard for Toronto to pull off.

I don't see Kyle Dubas resigning either Polak and Komarov. Thankfully, I should say. Moreover, I don't think either of them would get that kind of money from any other NHL team.

As for Doughty, I am not sure the solution is to seek out the most expensive defensemen. One (or two) defensively reliable RHD doesn't need to cost that much, and the team would be transformed for the better.

Finally, the weakness of the proposed lineup is the absence of a good defensive centre. None of the top three centres has experience on the PK, and defensive tasks aren't their strong suit. Aaltonen would be a rookie.
Moreover, the four centres are left-handed. The balance isn't there. At least, it would be an exciting team to watch!

I think if you can add a stud RHD, the entire defensive corps gets better as everyone else slots down a notch on the depth chart. Adding one or two decent defenders likely doesn't move the needle.