I've never thought that you had to wear french cuffs with braces. As you say, the pants should be accommodated for them and not have belt loops, and it's something that should usually be done with a suit rather than on its own.
In general, the rule is that the lapel width and the tie width should roughly match. I actually think, for a smaller guy, a 3" lapel works fine with a wider tie and can create a nice contrast. But that's because the lapels don't look disproportionately small. I'd guess that for a 45L a 3" lapel will look really small (kind of like the way the lapels on Mad Men look on Don Draper), so wearing a 3.5" tie with such narrow lapels would be a little off.
Agreed, the reality is that outside of big banks in NYC or actual fashion houses, people who really know or care about suit construction or a pair of fine leather shoes are few and far between. Even in big law firms, you'll regularly see people walking around with their old Kenneth Cole square toes and suits from JAB or Lauren Ralph Lauren. No one really cares about how you dress as long as it's within a (broadly conceived) range of what qualifies as professional attire.
So for members in the United States who ordered these, what was your total price per pair of shoes after taking into account shipping and all other costs (and does Meermin deduct VAT since we're not an EU country?)?
Re: the Parnis watch -- it's a solid choice and definitely a good buy at $100. I would advice you to be aware that Parnis watches are often "homage" watches (a nice term for watches that crib the look of a more famous maker). For reference, the Parnis you linked is basically an IWC Portuguese imitation.
This isn't a bad thing necessarily, and I love some homage watches (Steinhart's Ocean 1 looks almost identical to a Rolex Submariner and costs about 7% as much). But just...