Serpstat is a general SEO tool providing position tracking, backlink analysis, competitor research, and a site audit.
The keyword research identifies Google volume, competition, and cost-per-click rates. It also provides analysis on niche questions.
For backlink analysis, Serpstat gives a detailed report on referring domains, backlinks with historical charts, and a quality score or rank.
Serpstat also provides a site audit functionality, identifying errors and recommendations, analysing meta tags, headings, redirects, accessibility, and inbound links. It's error reports are detailed and instruct you on how to fix them.
The cheapest tier provides a generous amount of data at a price that won't put you out of business.