This is a set of talents I settled on awhile ago with Tracer, I have used it for nearly 200 matches in QM. It doesn't necessarily deal with her inherent vulnerability to characters with stuns and slows. Though it does allow you chase heroes down very effectively.

I would highly recommend reading the breakdown if you want to know why specific talents have been chosen. But here's a sort of TLDR with a few important notes:
- Don't waste blink use it sparingly with Bullet Time and you will have blink up most of the time. Especially useful for escaping after a rewind.
- Don't forget Untouchable is lost on death.
- Pulse Rounds works well with other basic attack talents, if you decide to switch things up be prepared for a drop in your Pulse Bomb up time.
- Total Recall has an increased cooldown be prepared for downtime that might get you killed if you rush back in.

This is me attempting to do my best at explaining how I like to play. I'm by no means an expert, if you want to play her different then by all means this is just my opinion. Have a good day.

Level 1: Pulse Strike
- Picking this talent allows you to build up your pulse bomb quicker. Allowing you to reduce the down time while maintaining your chase. Even if you don't get the chance to finish a hero off. It can prove vital in the next encounter to have pulse bomb ready.

Level 4: Untouchable
- This one is pretty self explanatory, this build is centered around chasing with your Blink and using Rewind to escape when necessary. Using this quest while avoiding your demise will allow you to build up your overall damage value. Especially useful since you will be breaking down health with your basic attack, maintaining distance to Kite them with your Blink. Then finishing them with a Melee or Pulse Bomb. Or a combination of the two.

Level 7: Bullet Time
- This is entirely preference, personally if i'm aiming to chase someone down I don't see an advantage to having a 4th Blink. I prefer to build up my charges as I expend them when chasing. If I had to pick between the other two I would pick Jumper. Since you cannot guarantee proc's from the Spatial Echo.

Level 10: Pulse Rounds
- The idea with this build is to use your pulse bomb as a finisher. So building that back up quickly is beneficial. I would take this over the slow since Tracer is extremely good at keeping up with most heroes without the need to slow them.

Level 13: Leeching Rounds
- This is again preference. I pick this to make sure Tracer has some level of heal to rely on to a degree. Especially useful without a Support hero on the team. The range isn't really a problem. As I said she is already extremely effective as chasing down enemy heroes. As for the Ricochet talent, in my experience while it gives more flat damage, I have had more use from Leeching Rounds. And it has helped to top up Tracer's health especially when you have low health. Are attempting to chase and the enemy hero's focus is on another team mate. A Warrior like Tyrael or Sonya for example.

Level 16: Focus Fire
- Part of the chasing is keeping a constant stream of damage. It will help to negate smaller healing effects being applied to the enemy hero. And when to whittle down the health quicker, ready for the finish with Melee or Pulse Bomb. This last bullet in the magazine also has the benefit of our Pulse Rounds from Level 10. Since it is damage done by basic attacks and not the number of attacks made. Otherwise I would chose Sleight of Hand but again this is your preference.

Level 20: Total Recall
- This talents plays into the idea of rewinding when in danger particularly if you drop to down health while chasing someone down. If you're careful you can hop out with Rewind, return most of your health and get back in there. So long as you remember the down time with your Rewind. Particularly with the increased cool down gained from the healing effect.
Get Stuffed! is less effective, we really don't want the knock back when the plan is to stick to the enemy hero like glue.
Composition B doesn't really have much of a benefit, since we aren't just throwing the pulse bomb into a crowd often the second one that is dropped will be wasted. The build often forces enemy heroes to run away, in this time using this talent would drop a wasted down on the floor. Where as Total Recall, prepares you for the situation where they might get backup and turn the fight around the last 3 seconds of chasing. Have now prepared you with a decent distance to escape to with most of your health and thanks to your Bullet Time, most if not all of your blink charges.