I see the point about how boring is to watch Monteiro. His matches normally are really long (and that worries me) no matter who he plays against and a part of his game is to defend a lot (but not just that). But who cares..., we like him, he fights a lot and has a really game and is improving it. Last year lost to Ghem winning just 5 games and now won. Not sure where he will reach, but he is doing well and I'm happy for him.
I think he needs to improve first serve though(including the toss).
Yes, exactly this. He should lift his game though if he is to become more than a Challenger player. His results these weeks are great, but all they show is an ability to compete on clay against other Challenger players. There are no signs of him being able to beat higher-ranked players or to perform on other surfaces.