One other question. Does anyone believe the i7 will add longevity to the machine over the i5? If I am thinking this will be around for 5-8 years, will the i7 age any better?
Right now we're nearly at an inflection point in Apple CPU performance for three reasons:
1) Intel may (finally) launch their 10nm tech next year
2) Apple may be working on a CPU alternative for their desktops
3) Local (as opposed to in-the-cloud) machine learning is becoming increasingly important, but requires dedicated silicon assets to do quickly
If #1 happens then the next generation of Mini that uses 10nm Intel tech will be a significant improvement over the current i7.
If #2 will happen at all I have no idea, Apple's A12X is impressive but not when you start to compare it to the I/O capabilities of a modern x86 desktop CPU. So I don't know how many years off a switch to ARM is for Apple, if ever.
#3 is a bit complicated for this post but it COULD (NOT will) become a must-have feature in the next several years, making any variation of the current Mini hopelessly obsolete without an eGPU.
Anywho, the point of all this is basically to say "yes, of course, but we don't how much" because the future is not clear. Get the i7 if you can on its merits now. The i7 is probably going to give you a 10-20% (or more) bump in performance compared to the i5 regardless of what you're doing.