Welcome to the forum.
I've made some progress last year on an ABA BAB upper/lower three times a week set up with moderate volume but the size were gains good and the strength gains poor for my size.
I'm considering going to a lower volume routine as I found a couple of years ago that I gained strength well on low volume but size gains were minimal.
Well now I've got some size I think it might be wise to change to a routine that's geared more to strength gains.
Welcome to the forum,
Initially you started out with strength gains but little size gains. Then you gained size but strength slowed down.
I'm not sure if somewhere along the line you improved your eating habits?
Strength gains will slow over time, so I would be curious to learn a little more such as some of your working weights. Would be curious to know your height and weight and how much size you were able to gain?
It's also helpful to know how you were focusing on progression of weight during these times.
Regarding workouts...The 3 day fullbody looks good. I would consider dropping one of the bench movements and adding in dips. You can't go wrong with dips.
The A/B split looks good as well. The only thing I am unsure about is wrist curls. I personally have never found them to be of much value.
Focus on progression and eating enough and either one should serve you well. Like Fazc said, focus on strength gains as well as eating properly.