I think he is, he is fast, skilful and has an eye for goal, he is like an inverted winger who likes to cut inside and chip in with a few goals.
You can never have too many good players, if he becomes available for around 30m, that is a bargain in my eyes in today's market. Sane, Sterling, Mahrez and Nolito competing for starting spots, i would sell Navas if we got Mahrez.
This would mean that we probably would not need to go in for another striker as we will have enough players to chip in and score goals to cover for Aguero. Sane can also be used as a forward anyway, i am sure Nolito could be used in that role also.