Thanks for the update!
I would like to address one issue and it's really simple, at least in my mind. Why Tron devs (or I can do it myself if you guys want it) are not creating a simple smart contract that will permit to people to use Steem VIA Tron, complementary as we do now with our Steem accounts. So the Steem blockchain could also handle transaction signed by the Tron wallets/users.
Technically we only need 1 and only 1 smart contract on Tron to be able to transact with the Steem ecosystem. And we only need a small change on Steem to accept those transactions!
From my opinion this is far the best option to keep those lovely chain as they are and permit interoperability between both of them. That will keep everything stable while giving an easy way to use/combine the Tron advantages with those of Steem.
This will not need any swap, any big change, only an a simple implementation in both side.
Edit : this option also give the possibility to have a dedicated TRC20/TRC10 for Steem on Tron. And basically we can give back the whole rewards for Tron users as SteemTron tokens or permit to users to swap their tokens at any time if they find it interesting.
This will work 100% and I can easily give more details if you are interested.