Residential Natural Gas Meter - Remove Fitting?
I have not adjusted the lines at the meter connection for many years because my gas utility got real upset (for reasons I won’t mention here). They started using J shaped fittings for higher system security.
If the utility is OK with you doing it I would since it’s on the customer side easy enough to leak check and it’s outside.
I will warn you with CSST you may not want a large flow device like a home tankless supplied (large flows tend to create a whistle sound) . Reducing the restrictions and elbows will help deliver the flow rate you may need but you may also need a larger meter if the oven, water heater furnace all kick in at the same time the whistle can be fairly loud go large to keep it from being a problem.