Diapers for skinny baby

Anyone else have a super skinny baby? My daughter will be 6 months on Saturday ( 😭😭) and she is very tall and skinny.. super lean lol. Anyway, she is in size 2 diapers and they are pretty loose. I have to pull the straps almost overlapping to actually stay on, and there is room around the thighs also. I never get pee leaks, but get tons of blow outs. I swear I'm scrubbing out poo stains almost daily lol. This has happened with two diaper brands - Rascal and friends and pampers swaddlers. Could I seriously need to go back to size 1?? Anyone else have anything like this happen? I have so many boxes of size 3's and she is almost 16lbs so just about in that range, but if 2's have been loose I don't want to try 3's. My current box is almost done so I'm just wondering what I should buy next...brand and size. Maybe I will have to buy a small pack of something to see if it works better for her.