With the spare 4 tons in that design, you could afford to drop some mass. If you drop an MG (sticking the other forward), you could drop the whole thing to 40t, reducing overall cost.
Or, you could switch to a fuel cell engine (since you're already using a higher tech cannon) and drop it all the way to 35t. Lower overall cost and easier maintenance (as a light vehicle instead of medium).
Or, use the extra mass to up the armor protection significantly.
Or, switch to fuel cell and include both armored motive and limited amphibious capabilities. Greater deployment potential and limits one of the great vulnerabilities of wheeled motive systems versus tracked.
Or, switch it to tracked, with fuel cell and armored motive, giving you an unstoppable armored box with a big gun. (But no longer a Hetzer-style vehicle.)
Plenty of possibilities there.