Baxter has excelled since moving to Boundary Park in the summer, scoring 11 times in 25 appearances, and last week committed his future to Paul Dickov's League One outfit on a two-and-a-half-year contract.
Simpson has largely operated in midfield this season with Baxter taking up his favoured role behind the central striker, but he is delighted to see the 20-year-old producing the goods.
"He's very good," Simpson said. "I think that role is the ideal role for him and I'm not sure he's had that at the other clubs he's been at.
"We've got a manager who gives him that freedom in that role to go and express himself. That's what he needs and that's what he's proven he thrives on. He's been brilliant for us.
"He's scored 11 goals now which has helped us be where we are in the league in terms of not being in the relegation places.
"It got announced that he's signed his deal before the game (against Brentford) on Saturday and the crowd's reaction was fantastic and the players are all delighted."