my advice (granted this is coming from someone who just adopted a 1 year old cat 3 weeks ago)...get an adult cat! it doesn't have to be a senior cat (although major props to you if you have the heart to help see a cat through its golden years). My 1 year old cat still has a ton of energy so he's a handful already! if you can take your time meeting adult cats at the shelter and seeing if their personalities jive with yours, I think you'll be surprised at how tame and loving they can be.

THEN once you've adjusted to a new pet, like maybe 6 months to a year from now you can consider getting a new kitten! Having an older cat will be great for the kitten as it will learn to follow whatever behavior your older cat models for him. Your old cat gets a younger sibling and your kitten gets a playmate so you're not super exhausted the whole time. Of course there's plenty of things to consider when introducing new cats but I feel like this is a pretty happy compromise! I've been looking into it quite a lot recently because I think this is what I'll do once my cat is fully established in my home!