Moira is ok, but her healing is not so great feeling.
I got raged against hard the other day because an Ana was outhealing me (on Moira). The DPS were all over the battlefield, so you know... unable to heal them. And when I did, it's much weaker now. He got the team to report me for throwing. It was the first time I've ever been trolled that hard. I switched to Brig for the second half and beat him on healing and he just doubled down and said "of course you'll outheal me on Brig." Whatever that means.
I decided to main brig (and off baptiste/moira, depending on match). This is something I did a few seasons ago when she was a raid boss. It's kind of insane the carry potential she has if you play right. I watch a lot of Violet, and she/he/they/xer are really insane at playing Brig. I try not to mimic her style, but I've picked up some good tips.
Was able to quickly crawl into silver from 1200 on support. Unfortunately my account tanked super hard over the seasons.