Hi, it all depends on how you feel in the suit. Can you move your arms easily when you lift them up? When jacket & trousers are too tights they start show to creases (I learnt that from my tailor). Your trousers look a little tight to me. I had a similar problem with mine and it was a matter of taking them to a tailor who let out the seat for me.
This. Always consider shoulders and back to be the first areas to assess. Many others can be adjusted, but shoulders and back are either impossible to fix, or else at an unreasonable cost. The upper back throws a few horizontal lines, which means that the jacket is either insufficiently wide in this area or that your shoulders (slope, typically) are slightly off the standard "template body" the suit maker chose to work with for the given RTW piece, or both. If you for any reason cannot return the suit, these horizontal lines can sometimes be smoothened by hiding a few millimetres of the upper cloth under it (relatively easy re-stitching of the neck seam).