been thinking if some Servants in F/SN or F/0 are summoned as pseudo-Servants (in their Sakuraface/Rinface, or dare i say, Shirouface form), it would look very ridiculous
and laymen like Shirou might have a bit skewed understanding of Servants (he might think that Servants' appearance is based on the body of their Masters)

it might lead to some interesting titbits like, if Shirou summoned Senji Muramasa as his Saber instead, then the two might be able to disguise as each others just by Muramasa wearing Shirou's raglan T-shirt; suddenly there is a grumpier & older-sounding Shirou running around with regular youngster Shirou
(not counting EMIYA Archer who is technically Shirou, but he already looks so different that nobody would notice)