Soldato
As he himself has said, Ferrari haven't been capable of winning a title since he moved so he's not lost out in that regard, and irrespective of how good the new one is they're going to have to massively improve in a number of areas over the last couple of seasons (tyre management, strategy, development) in order to mount any serious challenge.
His move back to Renault was out of necessity and his move to Ferrari nearly brought him 2 titles. The McLaren move was a gamble but I can see why he took it - I'm more surprised that Honda managed to negotiate out break clauses.
It's similar to Alesi, who on the surface made some infamously bad choices, yet when he rejected the 91 Williams seat (a move that would have likely seen him win at least a couple of titles in hindsight) to sign for Ferrari it was Ferrari who were challenging McLaren, not Williams. His move to Benetton again was a move to the top team, yet the 96 car was a bit of a horror.
I'd bet good money that Alonso will be sat in a Mercedes this time next year, and if so nobody could argue, at the moment, that that would be a poor move. It's surely the reason Bottas has only signed a 1-year deal (though I'm not convinced it will be Bottas leaving Mercedes - I think if Hamilton wins this year he might be off).
