While I certainly agree that a separate battery digital information/calculation device is nice (we also have a Balmar Smart Gauge), I would advise keeping the basic analog volt meter. Far Less to go wrong, at least not for 3 decades or so. When our factory analog meter finally stopped working I replaced it with a new (same) expanded scale meter from OEM supplier Newmar. Our panel has a toggle switch to read one bank or the other.
Good basic information, and the longer you own your boat the more you learn from this little gauge.
Maybe it's just me, but I like a hierarchy of information, with a meter like this anchoring the 'basic' start of my electrical info chain.
It's the 8 - 16 volt meter.
Panel Meters - Analog - DC Power Onboard