The part you didn't answer yet, is if you may want to use sqm - which is rather important for this WAN speed, as it is on the cusp between 'normal plastic router' and the (much better) better options hinted at by @frollic.
Let's take a look at the alternatives you mentioned:
- wrt3200acm, yes its wired speed is more than good enough for the task at hand, but its wireless side is in a sorry state, with serious bugs remaining open for years and the vendor no longer caring about the drivers (mwlwifi). Unless you already own one (as in, it's free), it's not possible to recommend this platform anymore.
- mt7621 is a kind of slow SOC, but with quite mighty hardware acceleration engines - meaning, what can be offloaded will be fast, whatever can't be handled in hardware (sqm, vpn, etc.) is quite affected by the relatively slow CPU. It's a solid entry level contestant, if matched with recent wireless chipsets (mt7615n, mt7915e, rather than the older mt760x variants or the quite special mt7613).
- let's add ipq8065 to the mix, which comes with a rather fast SOC, good wifi5 wireless and manages around 500-600 MBit/s routing (using swconfig, dsa is still slower (in the range of ~360 MBit/s), but there's ongoing development to speed it up before it migrates over), but sqm would drop that figure below 200 MBit/s (around ~190 MBit/s). Popular devices would be the Netgear r7800 or the ZyXEL NBG6817, for US based users the rac2v1k would be a hot contender, as you can find it starting around 20 USD on the used markets.
- mt7622bv+mt7915 would be the ticket into the wifi6 arena, currently the Linksys e8450/ Belkin rt3200 would be the top option there, it should cope with your desired WAN speed even with sqm - wireless should be good, but probably not quite meeting the range of the (wifi5) ipq8065 options.
- as mentioned before, you're quite close to the border between 'plastic routers' and So you have 500Mbps-1Gbps fiber and need a router READ THIS FIRST, depending on your outlook into the future (expected speed upgrades on cable/ fibre) you might want to take a wired-only router based on the RPi4, NanoPi r4s or x86_64 with dedicated APs into account.
I have no advice for cable modems.