Trying to choose between an iMac and Macbook

It ALWAYS comes down to 1 single question. Do you have an occasion to have a need for a portable device. If you do then forget the iMac and get either a:

MBP or a M4 based Mac mini and a travel display. Right now the MM for almost all users is a better choice than an iMac.

Just to add a bit to rkaufmann87's reply ...

... Your 2013 MBP is on its last legs. I would certainly not recommend putting any more money into it. rkaufmann87's suggestion to have you consider getting a Mac mini is a very good one. FWIW, I have been getting minis since the 2008 model. I have never regretted it. I currently have the 2023 M2 Pro model and they now have a M4 version with a whole new case design ... more like the looks of a smaller version of their Mac Studio devices.

One other suggestion that I would suggest, if it were me. I would get a Mac mini, but still consider getting either a refurbished Mac laptop from Apple or OWC. Unless your research has you doing intensive graphics work or system modeling simulations, you can keep your cost down by not going "all out" for the CPU. Keep in mind, the M-series Macs cannot be upgraded for either RAM or storage, so I suggest, at least, 16 GB RAM, & 1 TB SSD storage. You can always add external storage, as needed.

If you go with a desktop I recommend a minimum of 16 GB of RAM and a 1 TB SSD.

If cost is a concern you can get a Mac Mini M4 with 16 GB RAM and 1 TB SSD paired with a 3rd party 27" 4K monitor for $600+ less and a comparatively configured iMac.

If a portable drive that's easily carried with the laptop would suit you give this one from OWC (MavSales;com) consideration:

It's available in sizes up to 2TB.

Just some food for thought.

Question #1 ("What do you think should be the minimum storage I should be looking at?)

I would recommend getting at least 16 GB of RAM, and at least 512 GB of internal SSD storage. You cannot upgrade either after purchase.

If you are getting a Mac notebook, and believe that 512 GB wouldn't be enough to hold everything you want to carry around (plus a little free space), you may want to get a bigger internal SSD for convenience. If you can leave data at home (e.g., on drives connected to a desktop Mac or a docking station), you might be able to save a bit of money by storing some of your stuff on external drives.

In any event, be sure to make provisions for backing up your internal drive and any external "data" drives.

My two cents, if you have a need for portability I would forget about counting on your 12 year old MBP. It's obsolete, it can't be fixed, and it can't run any contemporary version of macOS or modern software. Personally I would consider the M3 MacBook Air with the 15" screen, 24 GB of unified memory, and a 512 GB SSD. It's $800 less than equivalent M4 MacBook Pro. Unless of course money is no object.

Question 2 ("Do you think it's imperative that I get the M4 chip, or would the M3 chip suffice for the kind of thing I do??")

In terms of computing power, I believe that any M3-family or M4-family chip could handle the sorts of things which you are talking about, provided that you have enough RAM.

If you think you would be interested in connecting two external displays to a Mac notebook, M3 MacBook Airs and M3 MacBook Pros with a plain M3 chip are not as desirable as MacBook Pros with a M4-series (plain M4, M4 Pro, M4 Max) chip. On the ones with a plain M3 chip, you must close the lid to use a second external display, and there may be limitations on the Retina scaling modes available on a second 4K display.

Older Mac notebooks with plain M1 and M2 chips can only drive one external display, period.

Good idea, go ahead and shop Refurbished Mac - iMac - Apple. Avoid the M1s - M3s are good.

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