LYuen
Member
Pendolino 390/1 coaches consist of 145 first or SP + 444 standard in 11 coaches, with 4 coaches in 2+1 seating400m trains would use 400m platforms. You wouldn't order them otherwise.
Freight trains can be up to 775m on the UK network, so a 400m passenger train isn't going to be a huge issue.
A 390/1 fits 589 people into 265m of train. An 801/2 can get 611 people into only 234m of train. The Azuma also has all of those features you mentioned on the Pendolino.
Azuma 801/2 consists of 101 first and 510 standard, only 2.5 coaches are in 2+1 seating
Pendolino is more premium heavy. If 2 of the first/SP coach on 390/1 is converted to standard, there can be 50-60 more seats