A lot of users have been here for a few years or months and put time into building their site. Some things you could think about adding include things like shrines (pages dedicated to things you like) or cool sites that you've found, things like that. That way like minded people who visit your page might follow you since you have shared interests.
A lot of people on Neocities including myself are trying to break out of a lot of the habits that social media have ingrained in us so if you consider your site for yourself first and everyone else second then you're on the right track.
There are a lot of ways you can make your site accessible, it is not really one thing. One good step is to make the site more accessible to everyone by making it responsive on mobile or smaller resolutions. Some other things you could look into for accessibility more specifically is colour contrast for text (https://webaim.org/resources/contrastchecker/), making sure images have alt-text...
Solaria wrote a helpful overview of examples of semantic coding https://solaria.neocities.org/template is a good place to start
Making a moving background paused by default and only activate on a button would help as well. Some people like myself have a visual impairment that makes me motion sensitive so turning off background animations help a lot.
np >.<