1) The pictures are indeed confusing. However, it is not a confusion with the Maxi set, as both pictures show 128 pieces, whereas the Maxi set has over 200. I rather think that there is an old and a new version of this set. The picture with 4 balls matches the one on the official Hubelino website, so I assume that this version is correct. But unfortunately I can't guarantee it. 2) The balls have a diameter of 2.45cm, so they are about 7mm smaller than a 2x2 Duplo brick. For a 14-month-old baby, the ball should be big enough not to be swallowed. But of course you should still be attentive. 3) The basic and maxi sets are still worth considering, as they have the extra long bricks (8 studs), which are quite helpful when you want to build bigger tracks ;-) But you can also build up the range over a longer period of time with different sets.

Picture four shows the elements supplied. A base plate is not included.

Absolument.