I find the logic - or lack of it - confusing, in that the sign with all 4 arrows (pointing left and right, and up, along, or down, to indicate which direction and which level each batch of trains is), should surely be between the platforms to your left and the ones to your right. As it is, the Eurostar arrow points away from the Eurostar information, and my first thought, just looking at the colours and the arrows without being close enough to read the text, was confusion. In other words, the arrows with the little person, and the Eurostar departures, should be the other way round. By the same token, since left-right correlates with top-bottom, then EMRT should be to the left of Eurostar, not to the right. Overall, I feel this has been designed to "look pretty" rather than to be as useful as it could be.
Similarly, if there are to be two clocks, rather than one in the middle, I think it would be better to have one at each extreme end rather than mixed up with what is, after all, a confusing set of information which needs as much logic as possible.
I take the point that if Thameslink northbound are running from the EMR platforms, then the display will be different to make that clear [though how?]. But what about the routine matter of the routes/destinations of some s/b Thameslink trains overlapping with the routes/destinations of some SE trains once they both get out of central London - surely some cross-referencing is needed for this too. And I agree with what's been said about the need for a note about some n/b Thameslink destinations also being covered by services from KX next door - there should surely be a separate subsidiary departure board with consolidated information for services to Cambridge etc?