dd2 uses a laptop in school mainly. she hasn't used a specific typing programme tbh, as she mostly just uses one hand/ finger! even the ot can't work out how she uses a mouse, but she does! she's better with joined up handwriting than printing, but tbh the laptop is much easier.
there are ots who can do it assessments though, so it would be worth asking if there is one in your borough?
aw, i remember dd2 with her walker/s. 
she still loves to dance now - we had to find a dance school that would take her at 4 when she still couldn't balance unaided. she hung onto a chair back for the standing exercises. for kids who take their walker over backwards, look at the r82 croc. it's much better than a kaye. like, a million zillion billion times better than a kaye. [grin
re research, dd2 has athetoid cp. tbh when she was little we used regular baby toys of the noisy fabric variety - scrunchy l(foil) layer within softer fabric etc. and physio and slt always had bucket loads of flashy toys from the pound shop.(those pen sized wands with internal lights - not the big long ones with heavy ends) and the squishy squeezy pocket money toys from hawkins bazaar. dd2 also had one of those fabric octupuses (octopii?) with the black and white checkered legs and different feet. it clipped on to her safety straps and was used well past baby stage.
whatever it is has to be visually appealing (especially for children with vi) light enough for children with little residual strenght to lift, and small enough for children with weak grip or small hands to manipulate. i say manipulate loosely - dd2 couldn't manipulate, it was just grip or no grip. and no halfway house. soft strands for stroking the back of hands to promote opening (lots of kids have trad fist or thumb in palm presentation and physio to relax grip is common - we spent hours and hours stroking the back of her hands to get her to open them). the best toy dd2 had was one of those uber light small rattles from elc. sort of bell shaped with beads in and a thin pencil handle.
as she got bigger, the best toy for therapy was a bog standard majorettes baton (also from the pound shop lol) with sparkly stars and glitter floating in fluid inside the handle. several got broken.... we used it lting on her back and then singing 'the grand old duke of york' to get full range of movement in her arms (hand over hand with me) from her thighs up to the floor over the top of her head. i wanted a lighter unbreakable one.
can i make a suggestion? you know the idea of a sensory basket? design lots of smaller things and a larger funky container or basket to keep them all together - a sort of therapy/ but fun kit in a box. then you can incorporate mirrors, squishies, lights and flashies, brushes - all of those things that we spend months amonths collecting and adding to the basket. design a blardy basket that comes with everything. parents could still add to it.
disclaimer - this probably exists already, but i haven't looked recently. dd2 is 8 now.
dear dear, i do go on. 
lovely to hear everyone's news!