At first, for 4 years, it was just a private and ecological meta search engine. But I didn't have the money to grow user base while relying on 3rd party APIs to deliver results. I had to create own index. I spent 1.5 years on web crawler, made from scratch in Rust btw. As soon as it was done it was able to deliver me 15M results a day on 200Mb/s download bandwidth. Which I'd say is competitive, especially as my next developmental step is to strongly improve distribution of crawling and let anyone help PriEco crawl the web.
About Goggles, it was the most wanted feature. I could have created my own system which would be simpler to implement. But I decided to adopt Brave search Goggles as they are public and sharable. I built on this idea with own additions as letting API customers use them in the requests, letting users export their full Quick Tune settings as a Goggle and as I adopted it from Brave search, they are cross-compatible both ways.
I base most of my decisions about PriEco on what the community wants. I just wanted a search engine that delivers on the 3 qualities I mentioned at the beginning. Otherwise, I let the community decide what's next to do. We have a Roadmap too. There you can vote on ideas and suggest your own. I'd like if you joined at least one of the chat platforms that are in PriEco footer. I run a bot that syncs the chats in the real-time so that we can discuss stuff.
That said as the index and ranking are completely independent, the results may not be great fit for everyone. I'm improving it as quickly as I can, so if they aren't for you yet, maybe in a week? a month? few months? Certainly I would like to hear about your problems. Also, PriEco does support DuckDuckGo bangs if it helps.
[2] https://codeberg.org/JojoYou/PriEco/