Maybe we can blame it on office rules that support a business casual wardrobe> Americans used to love wearing suits and you're usually frowned upon wearing jeans and blazers in the office. Now its everywhere!
^ He does makes sense. I fyou're planning to lose a few pounds it's best to hold off in completely changing your wardrobe unless you've maintained an ideal weight, then you can plan on going for mtm or bespoke tailoring.
The navy suit is a nice choice given that it's not your wedding but good friends of yours, a patterned tie, striped one would be a subtle addition to your suit. You never want to look overdressed than the the groom.