Upgrading from a 2014 MacBook Air for basic browsing, music studio work, and photo editing: M1 iMac or Mac mini?

As long as you're purchasing a Mac with Apple Silicon, you will be fine for your stated use cases. Be aware that for internal storage, you cannot upgrade that later so I'd suggest selecting something larger than the 256 GB base option if possible.

If you will be shooting RAW images, that can add up (for example, I keep the most recent 5 years of RAW files on my internal drive, and currently that's a bit over 100 GB). However, since the iMac is a desktop Mac you can easily add additional fast storage with an external SSD (e.g., a 1 TB SSD is <$100) and just leave that connected.

Obviously, you'll be giving up the portability of the MacBook Air. Personally, I use a MacBook Pro but when I process images I am usually connected to a large external display.

An iMac caution: the entry-level iMac (8-core CPU) )has only two USB expansion ports and no port for wired ethernet. You would have the extra cost of a docking station to get more USB ports and wired Ethernet.

The next iMac up the line, the 10-core CPU model, has four expansion ports and its power supply has a port for wired ethernet. It also comes with Touch ID, something I once thought daft but but now find it useful.

We recently ordered the 10-core for Mrs AJ and up-ordered it with 1TB of SSD storage. The base 256GB SSD is, judging from too many sad stories here, too small for even some light users. I see 512GB the bare minimum for many average users.As neuroanatomist advises, you cannot add RAM or storage later.