Don't think the 4700 shifters will work with a 10 speed cassette and derailleur. The pull ratio and throw is different between 10 speed and 11 speed. A front derailleur shouldn't matter that much, but a rear will. I'm sure some have tried it, but I wouldn't.

Max 32t will take a 34t cog. I ran a stock 28t on a 5700 short cage DR and swapped it out for an Ultegra 30t. Wound the B screw in and added a couple of chain links. Running a 50/34 compact up front.

Each added tooth changes the radius of the cassette by about 2mm. Wind B screw all the way in, measure the distance from the teeth of the largest cog to the lower jockey wheel. I had around 9.5mm gap between the 28t and the lower jockey wheel with the B screw wound all the way in. Was going to go to a 32t but got the Ultegra 30t at a good price.