The reason I didn't give a specific number is because it depends on individual use-case-scenario and average workload. If you're a power user and do a crap-ton of things all at once, the more the merrier. If you are a gamer and do little else, 4 would do the job well. Everyone has to look at their computing habits and carefully consider what they might need. It's always best to overshop to give yourself room to expand. So if you do a lot of everything, a 12900 model would be a good way to go. If you're more of a gamer a 12700 does well, if you're more of a casual user, a 12600 or 12400 would be fine.
No, I'm saying that Ecores compliment Pcores and take the light loads off of them. For example;
View attachment 237517
This is a screen shot of Windows 11 running on my recently acquired Lenovo Core2 based system, running an E8400. That CPU is roughly equal to 1.5 Ecores and it runs 11 perfectly(surprisingly) well and smooth, so a full 4 Ecores will be more than enough to run Windows by themselves. 8 Ecores will allow Windows to even more smoothly. Either way, this leaves the Pcores to do heavy lifting. The Pcores can then be power-gated(shut-off) when not needed leaving the rest of the system perfectly smooth and the user won't know the difference.
The reason I'm comparing the Ecores to the Core2 line of CPU's is because they are, from what I understand, very similar architecturally. While the Ecores are FAR more efficient in electrical power usage, they seem to be in the ballpark of performance. So IMO, it's a fair comparison.
Does this make sense?