AP is useless on Nami, since she scales quite poorly overall. Generally what is taken are Flat HP Quints, in order to just be that much more stronger for all-ins during early levels. Otherwise, MS Quints are useful as well. At the moment, if you take GP10 Quints under the reason that you are afraid that you won't do so well in lane, you are somewhat already putting yourself to be in a losing battle. I suppose if you really wanted to, GP10 Quints can work to amass you a lot of gold, but things like MS or HP can make much more of a different at levels 1-5.

Item choices that are missing are:

Twin Shadows, Frozen Heart, Mikael's Blessing, Spirit Visage, Morellonomicon, Liandry's Torment and Randuin's Omen. Possibly some others that I've missed out too, but those can all have a place inside of Nami's build.

Thanks for the input; my first guide, so I definitely could use some. I will try to address all the gaps you have noted and incorporate other build options soon. How do you feel about AP Quints? One thing I feel like with this build is I don't maximize on any AP/Utility scaling for quite a lot of early game. Also, I think my rational for using Gold Quints is geared more towards ranked soloq volatility, since if your lane is failing it will be harder to get gold and you will fall behind harder. Maybe it is something I am also experiencing more so at lower elo's in ranked.

Gold quints aren't really necessary anymore, especially if you're speccing 21 into utility. You can have more laning presence if you take something like HP Quints instead.

Basic information seems okay, but it's really just missing overall. I mean, what other items do you get (or can get)? There are other item starts that are available right now for supports (like just consumables + wards).

No explanation of your runes or masteries.