Do you require MBpro to now do the things you describe? If not, you might want to jump into the home improvement store and buy a basic Studio for a few hundred less than “starting at” (new). It will probably be a lot and most easily resold in a few years if your usage needs increase to tax the hardware.
If you tax the MBpro, things get more complicated. Obviously, the more power you get for the things you do, the faster you do some of them. So someone might be arguing for the whole MAX while someone else is arguing that the base unit is all you might need over a 2015 laptop. A lot of people here will say that this are the most powerful computers in the world and nothing comes close… but the reality is that they may be the most powerful Macs (in many ways) right now.
I upgraded to 48-core Ultra in a similar technological leap and am very impressed with the power when doing graphics and video work with it. I don’t think anything I’ve done has really taxed it, except maybe a whole bunch of Blu Ray conversions in Handbrake, converting 4 at a time to HEVC files while doing a bunch of other stuff. It was terribly fast compared to trying to do the same with Intel Macs… so fast that I was checking the first renders thinking they couldn’t have been converted as fast as they were.
There are many videos of media producers working with Studio on YouTube. Look at some who aren’t obvious koolaid drinkers and you’ll get more objective information about what they can do in your areas of need. The general message seems to be “incredibly powerful Macs” but NOT “the most powerful computers” (unlike so much going on here). Again, I’m pretty happy with my Studio, but don’t buy the hype when objective comparisons prove otherwise. It’s definitely the best Mac I’ve ever owned and definitely feels very powerful.
Try entering an Apple store. Chances are you can get time on some studios using whatever software you like to use. Take that time and try to get him to do things that usually slow you down on this MBpro. You will probably be very impressed. Maybe take on a complex project at a time of day when they’re less busy, then complete some of the intensive steps of the project using an in-store? This should illustrate the power much better than the opinions of the folks at Apple.
Option 2: Guess your need best, buy it, and test it like crazy in Apple’s return window. You can always trade for more power if your guess doesn’t match your wants/needs.
As for the 6-7 year longevity, I’m afraid macOS updates will make them obsolete even faster than traditional Macs…that they’re set to magically become “long in the teeth ” in just a few years to try to make us turn our computers like we turn our phones. We’ll see, maybe I’m too pessimistic? I also hope the >6 KI$ outlay for Ultra means I have a Mac that can also roar for 6+ years. I bet that will be have such legs but only time will tell.
From everything I’ve seen and read, if I could go back to launch day and order again, I’d probably choose MAX over ULTRA and the “midrange” as you say…although I would probably still pay way too much for a big internal storage upgrade from Apple. This IS quick storage and there seems to be a speed advantage that scales with size. I bring my internal projects to this fast storage to work on, then store them in slower connected storage when finished. Although Apple’s pricing is pretty much (fools and his money) a steal (IMO) on SSDs, I’d give it serious consideration over thinking about 1TB.
One more thing: for the kind of stuff you’re doing, perhaps the biggest impact ‘feel’ will be the choice of screen. Doing this stuff on a laptop screen versus a large or maybe even ultra-wide desktop screen should feel like a huge leap forward. I’ve upgraded to 5K2K ultra-wide and the extra RE over an older 27″ iMac display is night and day. Also be sure to think carefully and select your display. There’s many great choices for productive work…not limited to just two choices with a favorite logo on them.
And one more thing: since you’re replacing a laptop here, this thing isn’t very big…like a cube-shaped bowling ball (not). There is already briefcase manufacturers for those who would like to carry it like a laptop. If you think you’ll miss Mac mobility, this might also be an option worth exploring. Screen at work, screen at home and carry the computer guts back and forth.