There are a couple of ways to do the migration in addition to the Ethernet option you mentioned:
- Using an adaptor, you can connect the two Macs together with a Thunderbolt cable.
- Back up your 2014 MacBook Pro to an external hard drive using Time Machine. Then use this same external drive to connect to your new Mac and migrate directly from the external drive.
You've already realized migrating via WiFi takes forever...and it does, and that assumes WiFi didn't glitch at all during the process. (Not very many of us here recommend migrating using WiFi).
The first method (Thunderbolt cable) is probably the fastest, but does require a Thunderbolt cable and Thunderbolt adaptor.
The second method is almost (but not quite) as fast as the first method, and requires an external hard drive with your Time Machine backup on it. Migrating via Time Machine backup is pretty rock solid, and Apple's been using it for many years now.
(Personal note: Last year I transferred nearly 1TB of data from my 2016 MacBook Pro to my 2023 MacBook Air via Thunderbolt cable, and was amazed the transfer took less than 30 minutes).