Hi Florimonte and welcome to the forum

Personaly m8 i would go for a craftmate 330 which is more or less the same as the Craft Robo but is A3 in size.
Sorrt not sure what the size is for the robo pro version, but the craftmate 330 has the optical eye ect and as with it been a A3 its large enough for T`s.
As for cutin out on a larger
carrier sheet, well you cna get quite a few large ones. but i`m not sure if your going to use transfear paper, if so they i would`nt use the CR or craftmate, as i`ve tryed and it just messes up the system and papper gets caught all over the place and is none useable, and is a mess. They are a minature vinyl cutter so realy vinyl is best used, but if not useing vinyl with it then why not try out the self weeding kiss cut papper ? comes in A3 size aswell as A4 and is good. Reason i say get the craftmate 330 is that i have one aswell as a larger 30" vinyl cutter and i use the craftmate more than the larger one and has payed for it`s self with in 2 months. They come with a 18 x 12 inch backing sheet, so would do what you want. Hope this helps m8 