I do hope we see a little bit more of Richard E Grant. When he was announced I was hoping he'd be a regular.
possibly...
book spoiler - don't read unless you've read some of the winds of winter excepts from GRRM's website
in the books Arya/no one becomes an actress(mummer) in Izembaro's (Richard E Grant's character) company
it wasn't Mace Tyrell who visited Bravoss in the books but Ser Harys Swyft with Lannister guards so Arya doesn't kill a Kings Guard (which she has already done now in the TV series) but during a performance she seduces and kills one of the Lannister guards who she recognised from her time at Harrenhall
presumably since she's already killed a Kings Guard/Trant in the TV series and the party from Kings Landing has since returned after visiting the Bank of Bravos then that whole seduce/kill a Lannister thing isn't going to happen... but maybe there is something else they've got in store for her via having her join the theatre company
it wasn't Mace Tyrell who visited Bravoss in the books but Ser Harys Swyft with Lannister guards so Arya doesn't kill a Kings Guard (which she has already done now in the TV series) but during a performance she seduces and kills one of the Lannister guards who she recognised from her time at Harrenhall
presumably since she's already killed a Kings Guard/Trant in the TV series and the party from Kings Landing has since returned after visiting the Bank of Bravos then that whole seduce/kill a Lannister thing isn't going to happen... but maybe there is something else they've got in store for her via having her join the theatre company