The Sabre is not comparable to the Senna. It has about 50 more hp while losing over 60% of the down force. Very different in characteristics. McLaren even calls it a show car for the road, while they describe the Senna as a track weapon. The Senna was also developed under the code name P15 to be a contender in LM GTE, which ultimate fell through due to a myriad of reasons.
The Sabre only uses the engine and the chassis from the Senna, with little to no bodywork (and aero) carrying over.
Nobody will drive a Sabre and remember FH4 or the Senna. The Vulcan is a good choice since:
- It's British
- It's a high down force monster like the Senna
- It had its own Showcase against the Avro Vulcan in FH4.
What's odd is their choice to include both the AMR PRO and the standard Vulcan. They are pretty similar overall and the downforce increase isn't big enough to change the way it drives.