Feedback on Improvement to Tactic's Trainer Analysis feature

TL;DR Chess.com staffers, please add an engine addition where we can input and explore moves and lines that are not covered in the Tactics Trainer analysis "notes" feature with a changing evaluation. 

The long version: 

I enjoy studying tactics on Chess.com, but a feature I've always found lacking was the analysis board. There a few, and sometimes no, lines that deviate from the main tactical concept for those who want to study where they went wrong. Sometimes the lines given have errors or illegal moves in them. All in all, it can lead to a very frusturating expierence for when I'm trying to use the analysis feature for understanding where my thinking was flawed on problems I've got wrong (and I know I'm not the only one, as I have friends who have voiced this opinion). 

One of the things competetors and other tactics training tools have built in is an engine that can start from the puzzles begining point for analysis. That way, you can see the evaluation change, and the lines of play that might occur should different moves be input by the person studying.

I think such a feature would be excellent to add to Chess.coms tactics trainer. Admittedly, I've lately been going to other tools for tactics training, which bums me out. I enjoy chess.com and have been a member for quite some time. If chess.com want's to make engine analysis out of tactics problems part of the membership, I would understand. However, given that those resources are out there free of charge, I would hope it be considered to put it in as an upgrade for all users, as it would greatly enhance the tactics training tool as a whole, and thus, encourage those eager to improve to sign up and join this great website.  

Check out V3.  Your wish has already been granted by the developers.  That little icon that looks like a computer?  Guess what that does?

Very cool. "Play position against the computer." Not quite what I had in mind here, as it's not the user controlling both colors to test lines and confirm self-evaluation, but it's a great addition. Thank you for pointing that out about V3. I had been using and older version. 

You're very welcome.  Yeah I can see it wasn't quite ideal for what you want but as you said it's very cool.  Great way to practice trying to put away an opponent as well.