There are so many ways to go about this in 2023, but let me suggest a few things to at least put on your radar as you do your research.
And keep in mind everyone does this differently. But since you made it clear up front that OCS games are your key target, then IMO Amiga OS 1.3 on an Amiga 1000 is the way to go.
From your bullet points above you can address 3, 4 and 5 with a
Parceiro II, which will run you around $200-225 last I checked. You just slap it onto the side of your machine on the expansion port and power up and boom! Instant (and fast/stable) hard drives with the ability to move files from modern computers to your Amiga in seconds. You also get a real-time clock and fast RAM.
The device is hands down 100% fantastic. It also would remove the need for a Kickstart disk to boot your machine. And, it could even let you play around with OS 2.0 and 3.1 if you ever wanted to in the future.
If you want to add more Chip, honestly you're looking at a Rejuvenator. These can run north of $200 in parts alone, and over $415 US fully assembled (minus the Agnus and RAM you'd need). Installation is not easy and requires patience. But it's a total life changer if you really need/want that Chip RAM. My guess is you can live without it for the most part and the Parceiro will bring you 8MB of truly fast Fast RAM, so based on what you've said thus far that's where I'd start.
Just know that you'd need to do some minor modifications to your Daughterboard for it to work, and David Dunklee (the creator of the device) would walk you through the details.