There's no such thing as overkill, only extra overhead to do more things with. Hell, if you found yourself with a ton of excess resources and good cooling, you could run a distributed computing project like BOINC on some of the spare cores and help out some scientists.

You wouldn't see much of a bump in CPU performance, 6cores to 8 cores with a 200mhz clock speed improvement isn't ground breaking.

Going to 8gb of memory will give caching benefits.

But... That's all well and good. However. What I found the most beneficial on a OPi 5, and the entire reason I bought it over other boards, is the onboard NVME m.2 slot. Yes, the orange pi 5 can support 2230 and 2242 M.2 NVME drives at PCIe3.0x1 speeds, and it makes a WORLD of difference in performance. Like you would not even believe how fast compiling and installing software becomes when it's not bottlenecked by the ~500 iops an SD card can struggle through. SD cards are ungodly slow, and OS level writes tend to kill them every few months (they're not designed to handle that kind of work). Even the cheapest aliexpress M.2 drives, which I bought a 512gb KingSpec one for like $16, blow SD cards out of the water, and will last for YEARS with a typical pi's workload compared to the few-months of an SD card. Plus they're big enough to even do a bit of file hosting on.