You will need 1 Creator anyway regardless of what you do, so why not just buy 2 creators and you're done ?
Even if you've already factored in your 1 Creator, buying an additional 2 creators is a lot cheaper than 5 Explorers.
I'd be interested to look at your data and the visualisations you're trying to create though
I understand your situation and my company was in the same situation a few months ago. Purchasing 5 explorer licences when you don't have so many to make use of it is, indeed, a waste of money. We are a small team too and just needed 2 people to work on Tableau.
This is what we did. We bought 1 creator licence only. In this, there is a package of Tableau Prep & Tableau Desktop and Tableau Server. Once you make the purchase, the company will provide you two licence keys - One, for Tableau Prep and Tableau Desktop and the other for Tableau Server.
Now, out of the 2 employees working on the tool, one uses Tableau Desktop and the other uses Tableau Server. The back-end guys use Tableau Prep to clean the data. So far, we have not faced any issues and this solution is working remarkably for us. As we scale up and have more people trained, we plan to make a comfortable transition to adding 5 explorers.
I hope this helps.
All the best.