I'm a Texans' fan... so far the offense hasn't clicked and Dell hasn't yet got more involved. It's clear Nico is THE guy though. So far Diggs is getting short, underneath stuff. He had two TDs week one but had VERY little air yards and it's been a lot of 5-10 yd passes to the middle, albeit for big first downs. All that said, he should be very involved week to week because of those things, even if Dell gets going more. Also, I know Mixon had the big week 1, but they could struggle running the ball going forward as they've actually struggled run-blockinig, especially in the the middle of the line. So, if that continues, they will be forced to throw more.
I can't speak too much on Aiyuk. I know he's talented and his metrics last season were great but I've not been a big fan of his fantasy-wise. BUT, I do think he will continue to get batter and better this season as he shakes off the "rust".