I also made a power budget for everything based on measurements using a power meter where I could. Having a power budget is a good idea (if I do say so myself).
Lead acid deep cycle batteries shouldn't be regularly discharged below around 50% but you can push it a bit further occasionally. There's a relationship between depth of discharge and expected battery life - here's one explanation:
https://www.pveducation.org/pvcdrom/...acid-batteries
That battery will give you 40Ah accessible capacity, which should still last you all night for the modest equipment you're using. And get a decent multi-stage charger for your battery - poor charging regimen is another thing that shortens battery life.