This thinly veiled advertisement gives me almost no confidence that the posting firm has ever met a data scientist much less possesses expertise in how to effectively recruit and build a function for them at a small tech company.

The first things to understand is if you are hiring for a DS role to support product development/understanding, growth or marketing, advanced BI, core product features (eg ML in your offering) etc. What VP your DS would report to in a 500 person version of your org chart makes a huuuge difference in understanding what skills and aptitudes you are looking for.

Design the position and responsibilities now and in 2 yrs for the ideal candidate, then design your hiring strategy.