A:AnswerI'd suggest time share backups from you old computer. If you don't have them, set them up. I use 2 redundant external drives for back ups. If you don't already have them, then set them up and use them a couple of days before you migrate to the new computer.
A:AnswerProbably not. I bought my 24" iMac in November 2024 and one was not available then.
Its 24" screen is too tiny for some things I want to do. Unfortunately, I had to upgrade because Apple, Adobe, and Microsoft had stopped supporting my 27" Intel iMac.
If you can live with whatever Mac you have a bit longer, maybe Apple will release a 27" iMac and offer it with a 1TB SSD.
If Apple makes a 27" iMac , I will trade-in my 24" one.
A:AnswerI use 2 redundant drives for timeshare backup and 2 really fast (ssd with thunderbolt connections) for my pictures. Those were hard to find. They are rugged mini ssd by LaCie. The second LaCie drive is just a redundant one. I edit photos using Photoshop right on the drives. It's extremely fast.
A:AnswerI don't think you can upgrade once you have the 512. I use external drives with ssd and thunderbolt ports for speed. They are fast enough to work off directly.
A:AnswerGiven everything you've said, I would look into a Mac mini or a Mac Studio. The apple studio monitor is quite a bit bigger. External drives are also a solution, particularly if they are ssd with thunderbolt ports. It's a cheap fast way of extending your storage space.