hey we can see this jpeg quality bugs. we will be releasing one update. By default it chooses intelligent quality means algorithm decides best compression quality for each images so we advise dont change plz but it should work and we are fixing this.
Apart from this intelligent crop decides the best thumbnails size. for example if you have 1024x800px images and you are generating 100x100px thumbnails then the full area may not represent right thumbs. for example some celebrity photo. in that case intelligent crop will choose face instead of full photo. we are tweaking that feature at our end so we have disabled manual selection by our users and we feel that, at our end we decided better than users selecting manually. did you notice one more feature, center , top and bottom option in listing of images?? you can decide where the focus of images is.
thanks for reporting. if you face any other issue plz feel free to report.