I watched your replays and here are some general thoughts I had instead of a timestamped replay breakdown. You are aiming your shots fully when you can, keeping your tank healthy and in safe positions. That's a good start. Its clear you are playing on the safer side of the safety/aggression spectrum. So to find the additional assistance you want, the place to look will be the more risky plays that you might not be seeing as easily. The unfortunate thing about looking for plays that are more dangerous than your normal comfort level is that you will make mistakes and die as you learn what is too much and too soon. The benefit is obviously that you will come out as a better player overall when you can walk that fine line more efficiently.
Looking at your overall T49 stats shows that there is some extra damage out there for you (1537 current average as I'm looking at it). This could be accomplished from turning one of your hits per game into a pen via being aggressive when it is safe to do so; or splashing for more damage by aiming for turrets or super structures that are positioned above thin engine deck armor (see the splashing engine deck post by @dualmaster333 in the Sheridan thread)... or just hitting an additional shot. There are also a few percentage points of win rate that you can improve via that higher damage per battle which I just mentioned or alternatively more assistance damage like you referenced in your title. I wasn't able to see your average assisted per battle or your overall hit percentage in your T49. Post those numbers if you'd like, so we can see a bit more information. Also, generally speaking there is less to give advice about when you link 3 ace tanker replays. Show me replays where you lost a semi close match. Show me replays on Steppes, Airfield, Ruinberg.
In the most simple terms.. to get more assistance damage you should position yourself wherever there is the most enemy HP remaining. For example, in the Malinovka game you made an effort to drive all the way up the hill to spot a sub 100hp T30... you could have used the amount of time you spent setting up and coordinating with your team to re-position to the other flank that had a full HP med and 2 arty. Let me take a moment to say that I think getting that T30 out of the game was good, but if you are asking about damage/xp/assistance maximization that is an example of something you could do differently. In the fiery salient game you did a good job of playing the hill and being responsible for winning that flank. However as far as maximizing goes there is generally more to be soaked up by playing the middle, between short active spotting runs and jumping back and forth from positioning to shoot the hill and shooting the 1-4 lines and possibly even getting the E1 bush at some point in the mid-game.
The main thing in the 3 games you posted that I didn't see you do is switch your flank fully from east to west when things stall. I don't know if that is a play you are comfortable with and just didn't see a need to do it in these games, or maybe something you could use more. Impacting more than one flank by using your speed is a great way to get more out of your games and light tanks are the best at being able to pull that off. Another big thing you can incorporate is forcing a booty shot situation when you know an enemy is isolated. If they are sub 900hp you don't even need to have an escape plan! Keeping a count of enemy tanks or using a mod to do it for you is a great way to see these opportunities in real time.
That's all I've got for now. I'd be happy to check out some more replays if you post them