I always think that the first 'solo' album was Making Movies when production and leadership are in his hands, with the band name, like Gilmour in the era post Momentary lapse.
Remember Ed said that Dire Straits is the vehicle for Mark's songs. The solo career begin after On every street that not had continued the Brothers in Arms success, after a long tour, when he was asked after a concert in Paris of that tour if all was done for money (remember 24 heures documentary) just above his hotel room.
When new bands like Gun's n Roses and Nirvana take success in the world I think that Mark had say ^stop' with long tours and continued played his music with much liberty only for us, his true fans!!