I have only had nano tanks in my time in the hobby and it fits well with it my budget (averaging $50 per month) and timeframe (personal and work life).
As mentioned by the member above, it all depends on how invested you want to be with time and financially. I would love to make my max nano a bit more automative to support my business travels but I am pretty good at staying within my budget. Still saving up!
Currently spending 30-45 mins per week max on maintenance (water changes, parameter checks, mixing water, etc). Every day I do spend about 30-40 mins drinking my coffee admiring, feeding, cleaning the glass, and changing out filter floss & socks.
Be mindful smaller tanks could have rapid swings in parameters if something goes wrong. Larger volume tanks have fudge factors built in.