It is a nice ranking tracker. We love the simplicity. Basically we would suggest to use one account for one domain. You'll reach the 100 keywords very soon...

Pro: - nice ranking tracker, love the simplicity
- awesome page speed. I'm impressed, what's your backend btw?

Con: - with 8 keywords we have already reached 32 of 100 keywords for tracking. Because of desktop, mobile, google and bing per keyword.

Some suggestions:
- add an amazing keyword search tool
- add an amazon product ranker
- maybe add suggestions how to improve the ranking