I really like Javelin and everything else about her character is just fine (pretty excellent actually), but as others have put it, she is a little bit on the cheesy side.
This might be hard to articulate with just words, but here we go…
My proposal is that instead of a direct fire rocket launcher (where the rocket travels straight from the launcher to the target), how about the launcher fires at a fixed angle upwards (sorta similar to a real FGM-148 Javelin, but not really).
Then, you would indicate where the missile lands via marker on the ground that everyone can see (you can still actively guide it to its destination like how the guided mode works now). That way, like a flare, the rocket gets a period of high visibility before it destroys its target. Additionally, the enemy (and friendlies in ranked) can see where the rocket is going.
The difference between this idea and, say, an Arty strike is that you can change the amount of time before impact simply by being closer to the target. Also, the player can still track targets actively with the missile.
The only problem I see would be that Javelin would be harder to use indoors, but I’m hoping other people might have some good ideas on that.