I am sure you heard about ICO market value, billions of dollars.
ICO listing sites are the primary directories for an investor to make a decision for buying tokens. Like Google says, to control the market you need to aggregate everything. So the idea is simple here. You aggregate ICO listing sites.
Maybe create a rating index for all listings. Then you could sell premium places for them, earn from affiliate marketing and banner advertising. It's a fast way to get into the cryptocurrency market and occupy a wealthy niche. You will collaborate with powerful projects, be the media partner at crypto events and join the closed community of rich people.
Cryptocurrency industry is going to grow again in the 2019 year, after some big banks will prepare infrastructure, will buy crypto for low prices, and start playing with bull strategy. Believe me, I saw how many funds they spending now to be prepared, they are smart people and they will never spend millions without understanding and predicting success.
I personally make a lot of projects in this space, so just don't have time to make
icoallratings.com, but I believe it will work. Cryptocurrency industry is live for more than 10 years, it's already proved efficiency and Bitcoin is going to be the future for everyone, maybe not as a paying instrument but an investing tool (like a gold).
My advice: just run a simple CRM (like Wordpress), create the template (similar as ICO listings maybe), write some articles on the topic of rating ICOs (for SEO), share the website at social media and forums like bitcointalk. You can also write to ICO listings and try to sell them your service right now. Just tell if they don't hurry, you will have a queue to be placed very soon. So, you will spend some time on preparing your website, then it will work auto mode.
I wish you all the best!