I think, I understand your solution. I think there are security holes which you won't cover and by that I mean, thirdparties poor security. SteemConnect always trust thirdparties, my solution does not. With your system even after adding IP verification there is always possibility hackers will brake on thirdparty server and send some transactions with usage of stemconnect token.

I think it could be devastating for trustment to any thirdparty.

Your solution does not provide live transactions options (and because of its nature its good), my solution can provide it.

My solution assums very limited or even no trustment for thirdparty webpages, you never know how poorly they could be done.

I understand disadvantages of my solution, neccesity of installation, not ful cover of mobile browsers and no possibility of server side processes (like automated voting), however if you want give someone your private posting key, go ahead and do it there is no need for steemconnect I don't see a big threat in that. I gave my posting key long time ago to
steemvoter.com

I treat security in blockchain technology very serious and I think when more thirdparties will occur and more upvotes would be stolen, people may really stop trust your solution, although the thirdparties will be responsible.

What you think about my opinion and concerns?