I think a good natural progression from excel is:

Those would be two tools that provide graphing capacity beyond what excel can do but still within a relatively user-friendly interface. So now you can take your excel data and plug them into those two :) RAW - http://rawgraphs.io/ and then Tableau Public - https://public.tableau.com/s/ (unless you're a student, then you can get tableau desktop for free, which let's you save local files too)