1k into a pooled fund as a first step, or is that too small to bother with

It's worth the 1k, and for the reason you already named. You won't learn anything about returns at that size. You will learn what their quarterly statement actually shows you, whether distributions arrive when they say they will, how the tax document looks and when it shows up, and how long a redemption request takes to process. That last one you can only find out by asking for money back, and I'd rather find out with 1k in than 20k in.

On the penalty window, check whether the discount applies to the whole balance or only to shares held under the threshold. Most of these run it per share lot by purchase date, so if you add monthly, each contribution starts its own clock. That changes the shape of your test a lot, because it means the 1k you put in today is free and clear years before the money you add later.

One small thing. Ask them in writing when the tax document is typically issued. If it lands after the usual filing deadline, that affects how you handle your return, and how you deal with it is a question for whoever prepares your taxes. Better to know that in year one at 1k than in year five.