1:13 You got hit super low and turned away from facing the enemies. In this situation I would of swapped to heals immediately and used the wall / entrance you just went through as cover while the rest of your team catches up and you regenerate some health.
1:35 You are waiting for the rest of your team and even making the call in voice chat, This is great on your part. Bad on the teams, nothing else you could of done in this situation but you made the right play.
2:16 Unless you are actively trying to dodge ability with speed or push, I would suggest sitting on heals especially in that super tight area where the majority of your team should be able to receive it.
3:06 When your ally zenyatta in tranq'ing sit on speed because you won't need to be healing.
4:00 You and an ally are chipped on health, I would switch to heals because you aren't actively trying to go anywhere right now.
4:13 I don't understand why you dropped the beat, You don't know whats behind the wall and your team is pretty healthy at the moment.
4:30 Wall ride a lot more, you are in an enclosed environment where you could benefit greatly from it. It's much harder for enemies to hit you when your speed and pattern changes constantly
6:00 Mei is one of the characters you don't wanna get up close to as Lucio.
6:50 Unless you are actively doing something You should be with your team.
7:10 Watch your ammo better, could of been a triple boop
8:20 You gotta stay more aware, You didn't know 4 people were to your left and almost died for it.
9:30 You are on speed when you should be on heals.  Your team is in a tight spot on overtime without the point in the middle of a fight. Healing is way more important then speed right now.
11:30 You should be wall riding a lot more when in combat, especially versus a Reinhardt and a mei.
12:20 I feel you don't know whats going on in the game right now, So you are just randomly firing and picking targets as you hit it works out since you get the mercy.
13:20 This is twice you got hit by Reinhardt ultimate in the same spot. You really shouldn't be getting hit by those since you usually arent the target and you can be on the wall high up.
13:50 You called junkrat on top by hes outside, way different area.
14:30 nice drop to save your team from ice.
dva game play lets go
16:00 You don't need to hold defense matrix on things you can't block. The mei or the Reinhardt shatter
16:20 Good escape and you save yourself at 50 for your mercy to heal you for rezz charge.
16:35 You went in early without the rest of your team by going through the window, you should hold up and wait.
16:45 You switch to zarya which I personally like since you can do more with a bubble here then a defense matrix.
17:40 You should try to bubble yourself next time. Building your charge and denying Reinhardt ultimate build up.
18:30 I liked how you tried to jump into the charge after bubbling when fighting the Reinhardt try to back up since your other reinhardt is his attention. You are just taking extra damage and feeding his ultimate there.
19:30 Nice 3 man grav, and your Reinhardt hits a nice 3 man shatter after. This may of been overkill as a team though since the enemy should have ultimates. This isn't your fault since you used your ultimate first and the Reinhardt should of been aware. You could of also communicated this to be sure but it happens in solo queue.
20:00 I would of thrown a bubble to someone on the other side mainly because you see people in the Mei ultimate and someone else being swarmed.
20:10 I would of waited for mercy rezz or died so you could of been in the 3 man rezz before of going into that.

General thoughts:
You did great trying to communicate with your team and you made calls when no one else was talking. I still think you could of done this a lot more but you still did some.
When playing lucio on the start of each point You would speed boost about 3-4 seconds after coming out and walking to the point. This isn't that great since The speed boost wears off before getting into the fight so your positions are relatively the same, but the enemy lucio now has amp in the fight before you get yours back.
I started to type less at the end because a lot of your mistakes were from the first two rounds. I would say to read those heavily and realize when in game you should be doing them and when you shouldn't.
Also I know a lot of lucios say sit on speed and I say that too. You sit on speed way to much and there are times when you should definitely  be on healing.