Moving Data from current site into SS

So apparently importing is extremely limited into SS, but I do have to maintain historical data from the old site into the new.  After some head banging I've come up with the following:
 

• Export data into a spreadsheet or CSV file from old site
• Create a SS form with the same columns or close to what I just exported
• Let SS create spreadsheet on Google Drive with the fields aligned to the new SS form
• Copy the data from the exported CSV file into the SS created, linked spreadsheet making sure the columns and data line up
• Now, when new forms are submitted, it'll automatically be added into the linked spreadsheet with the historical data

I can now create pivots, filters or other capabilities to manage the data, both new and historical.

For example:  export donors and linked donor donations, by email.  New donations with information would be added into the same spreadsheet I just copied data into, I could then create a pivot to report on donations by year, month, etc. that would include historical and new.

Does anyone see issues with this approach before I get too far down this road?

I exported the volunteer data and formatted it to align with the form/Sheet from SS into Google Drive (storage), created a Pivot on the data and it appears to be worked perfectly.

So I guess from these experiments, that the approach of SS isn't to literally import "data" into their platform, but be able to align form data to a spreadsheet to some sort of cloud-based storage that can then be managed in whatever format from that point.

Interesting approach.