Personally, I think
1. The sleeves are a bit too short.
4. Jacket is a bit too short.
2. Pants don't drape too well. I think they're too slim?
3. Somethings up with my shoulders. Don't know what...
What do you guys think of the waist?
The tightness over the arms comes from the second picture at the top of the arm by the shoulder where you can actually see an horizontal indentation where the shoulder starts. This is always down to being slightly tight across the arms. It may not feel bad but letting out would ease this.
I would hazard a guess that if you had a photo of the back then there may be lines in between the shoulder blades too but not 100% certain. Educated guess.
Distinguishing the lines is like working out an illness from the symptoms. I have seen this on enough suits and arms (talking about the diagonal lines down the sleeve) from there it is reasonably easy to such a suggest how to fix.
posture is a lot of it but simply put that is fine for off the pegs as they are made for a general fit but tailored an be better than that.
Also have now noticed that the suit trousers are catching on your calves. This is causing the wrinkling on the bottom. Again this isa body thing and may never dissapear but can be adjusted in future suits of your tailor knows about it.