Contrasting buttonholes: ostentatious?

I'm having my first nice bespoke suit made (at WW Chan), in black Zegna wool. I want the suit to be rather flexible in use: appropriate for business, weddings, etc., the jacket perhaps usable on its own with nice jeans, etc.

My main question is essentially whether it is tacky to have the buttonholes -- specifically, the lapel buttonhole and the first (of four) buttonholes on each sleeve -- sewn with light grey thread to match the lining. I assume the contrast would be fairly noticeable given the darkness of the fabric. Is this subtly playful or does it just scream that I'm an arriviste jackass who wants everyone to know my clothing is custom? I need to let them soon, so any thoughts are appreciated.

I went with 3 buttons but am undecided as to whether to roll the lapel. If so, I'm thinking 2.5. Any ideas on how that would look with the slim lapels I requested?

Thanks!

Thank you all for smacking some sense into me. Really don't know what I was thinking. No jack-arr contrasts for me.

I was hoping for an interesting lining , though I doubted they'd have fabric with an Etro/Paul Smith-level of flash. But basically they said, we used Zegna linings with Zegna fabric; here is the spectacularly boring range of plain colors you may choose.

OK, survey says: kill the contrast. I think I'm going to add a vest to give the suit greater formal flexibility, so I guess the idea is even worse now than before. Thanks again for the advice.