Weddingbee boards

I'm also wearing an ivory dress & was really worried about this, too...

I don't think it sounds like you have too many colors at all! If your FI is wearing a black tux/ivory shirt and your son is in grey/ivory, your men are in grey/white/purple, it sounds like your son & FI should wear purple, too. Or, you could always try to find a tie with a striped pattern or a subtle pattern that includes all of, or some of, the colors you're using.

My FI knows nothing about my dress, including color but my maids (and Men's Wearhouse) all said ivory and white would look fine together, so the groomsmen are all in black tuxes with black vests and striped black on black ties. FI is wearing black tux with grey vest and grey on grey striped tie; all in white shirts and purple pocket squares.

Good luck! Whatever you choose, it will be beautiful because it's yours!

When I was considering an ivory dress, the woman at the bridal salon suggested we keep the groom and the groomsmen in white shirts but place the groom in an ivory tie and vest with the other men in a different colored tie and vest.

I am sure whatever you chose will be great!