A half inch would be safer. There's nothing wrong with showing a little cuff. Just make sure you're not wearing a shirt that's too long. It then just comes off as being part of your style and not "wrong".
Only go on-line MTM as a last resort. Until you get used to wearing a suit and what it should look like you'll have a hard time just evaluating the suit you get for a remake if it's not perfect out of the box (which it most likely won't be). You may also want to get a slim fitting 36 rather than a 35 for the extra length. If it's a 7 inch drop, then the pants won't be too off. Try a few bodies and see what works. You should get some good help from their staff.
Agree, the Suit and coat both look great. I have a couple Soho cut suits from this season as well (the navy and charcoal from the site) and both are fairly heavier weights as well. The Navy pinstripe is cotton and a little bit lighter weight. I love both of them and am now contemplating getting that DB coat as well.
I agree it looks a little tight. It may be the way you're standing. It's hard to tell with just one photo. I don't know if having a long would help though. If it's too tight in one lenth, it is usally in another (unless it's due to where the buttoning point is). Overall the length looks good though since the sleeves sit where they are supposed to and the jacket is meant to be that short. May just want to have it let out a little.
So much is in how you wear things.
Whatever you are putting on that has a bit of flair: if you own it, you will look powerful, if you are trying to pull it off, you look weak and like a poser. Wear what you love, love wearing it, and people will love it ion you (unless you look like Krusty the Clown).
They guy on their explanation of what a "Soho" suit is on the site is wearing a navy suit. You should just contact them and see if there is one available. If there is I can't see them not wanting to sell you something.