Any deviation from base specs isn't "worth" it and especially these too CPU's since there performance is negligible.
Apples profit margin increases exponentially with upgrades. That 300 dollar CPU upgrade actually cost you 300 dollars + the i5. You can find the i7-8559u in ultra small form factor PC's that have a TOTAL cost of 499, (I couldn't find Intels retail on it).
I can't even confidently recommend 16gb of RAM however I do feel you'll be better served by it.
I have a 2018 MBP i5 8gb ram 512gb SSD. Generally I wouldn't have got less than 16gb of RAM, however I got a good deal so I said to heck with it.
So far I've been very happy, surprised even. My workload consist of 10 poorly optimized web pages in safari tabs, email, messages, FaceTime, and photos which I still have open. Currently though I'm using Gimp to edit photos which I'm importing into iMovie with my work stuff still open.
MacOS is virtualizing RAM (swap) and its compressing a lot of data. However I wouldn't be able to tell you that without looking at activity monitor because everything feels smooth as silk, or at least as smooth as those programs feel being the only program open on a fresh boot.
Now I'm not editing RAW nor am I using HEVC codec however I feel I need to be reasonable since those task are more professional workloads that you'd want more than just 16gb RAM (dedicated graphics, larger SSD if you working locally, etc).
Future proofing a Mac is silly IMO because MacOS support is dropped arbitrarily based on the model year. An obsolete Mac that is 20% faster is still obsolete. While there is a quality of performance leading up to the planned obsolescence I've never found the maxed out model to be night and day compared to the base model. That is just my experience and opinion though. Its a free country, get what gives you that warm and fuzzy feeling.