Specific Gravity varied widely after topping up.

I always get a little less SG in the cell nearest the neg post. No idea why. I just ignore that.

I agree with others to seek a warranty relief if it exists. If not, and you are on shore power mostly these days, then you don't need much battery.

That leaves the question whether your existing maybe crippled somewhat batteries are good enough for being on shore power as is if you look after them from now on , or whether to spend new money.