I don't think your cpu is the issue here. It could be your ram is the problem. Luckily ram is easily upgradable. Typically 16 gigs of ram is the bare minimal for gaming but things are moving fast towards 32 gigs.

If your ram is at that level, your gpu or on board graphics may be the issue. A gpu / on bard graphics capability is typically the most important component when gaming.

One thing you could use to check is game bar (windows + G) and pinning the resource usage window while in game to see what has high usage.

Games maxing out vram is a real issue in general as of late. As a laptop gamer myself it is hard to go above 1080p even with newer laptops simply because there is hardly ever enough vram.

Other things that use vram, on top of resolution, is texture quality. Higher textures use larger files that clogs up vram.

Another thing to look out for is the temps of your cpu and gpu. If you are seeing dips in performance late game that could be a sign of higher temps causing a crash in performance.

Either way a newer laptop should perform quite a bit better and it sounds like you made a good purchase in regards to where your current laptop is in its lifespan.

To answer your question about cpu, yes you should still see a benifit from an upgrade there. But gpu is also still important.

yep the upgrade fixed the problem. I get 0 lag at any stage of the game.
I only experienced a little bit of lag once when we had a 17000 supply of units fight in a 5v5 game but even then, the game was still playable, i still was able to command my ships and play effectively. this was on max graphic settings.

regardless i think it would be wise to allow lower settings so people with slower cpu's can play a 5v5 game.