But I don't see the issue here at least where Nami is concerned. Both non-AP items are still godly on her as it means you can spam your shit. After SS, Ascension and Chalice/Mikaels I either go Mejai's or Ruby into Guise. I'm not sure how these are selfish at all?
well for starters mejais idiotic, even PMD sells it every single game, he builds mejais to troll dude, don't follow what pros do blindly!
but look at your final build
shurelya, ss I suppose is sorcerer shoes (why? get tabi or merc or mobi, they're all 10x better on nami!), then mikaels. now you have 3 slows left, you never bought sighstone and you spend around 2.7k gold on a 0 stacks mejai+haunting guise. you're left with a single slot that can be either used for sighstone or pink wards, but you can't have both so if it's baron time, your team must have better bought some red trinkets or a shit ton of wards to compensate you not being able to do your job.
if you want ap just get a morellos dude. it caps you out on cdr and it gives you a passive that helps your whole team. you're stacking penetration with sorc shoes and haunting guise for a champion that has really shitty non-spammable base damages and you're buying mejais on a squishy squishy support
I'd say you need to rethink your build
btw my build right now on everyone but leona:
start: doran shield + 2 pots/ward + ward trinket (unless I'm blitz then I like to start coin)
first base: coin + pots and wards
second base: either upgrade coin, get a full sighstone or get chalice. depends on the lane, I'll only get sighstone is laning phase is already over and I won't be sitting in lane to make much use of upgraded coin. chalice is if it's a poke lane or I'm afraid of the annie or something.
after that I'll build like most people shurelyas > sighstone (sell trinket, get red one) > mikaels > ruby sighstone and stick boots somewhere in the middle, usually defensive boots, but sometimes mobi or swifties.
after that all tankiness, usually a randuins first, but also spirit visage, banshees, etc.
I'll always be buying pinks and I'll eventually upgrade the red trinket.