Matchy Matchy Renfrew

オットのロンTを作った残りの布で自分用にカットソー作りました。
型紙はカナダの会社のSewaholicさんとこのRenfrew。この型紙使うのもう何度目？

オットとペアルックにならないように気をつけないとね。

Since I re-cut MOTH's long sleeve T shirt when I raised the armhole and I was left with big enough left-over fabric, I made myself a matchy matchy shirt.

The pattern is Sewaholic Renfrew.
The fabric is rayon jersey with Lycra. The thinness and the drape is perfect for the cowl neck.
I cut a size 6, shortened bodice by 1", but lengthened sleeves by 1" (for winter weather).

I love this pattern and I have made a few Renfrews in the past. Actually, this pattern was my very first sewing pattern purchase a few years ago: the pattern that started my garment making attempt.

I'm pretty sure size 6 is where I should be and I am pretty comfortable and really like the fit.
HOWEVER, every time I make this shirt, I get that whisker wrinkles from the armpit above the bust. I am totally fine with all the excess fabric at my lower back (I'm not going to do a sway back adjustment for a T-shirt) but I do not like the whisker wrinkles at the front.

My fitting knowledge is limited and I do not know what to do with it. I'm thinking that the front bodice armhole is too long? The Renfrew's shoulder curve is symmetrical unlike the normal shoulder curve which is longer in the back. Do I need to go up a size?