After back-to-back relegations in the previous two seasons, many pre-season predictions had Wolves running away with the League One title under Jackett's shrewd watch.
The midlands club currently lie third in the table after picking up 22 points from nine games, yet McDonald insists the best is still to come.
"We've kept ourselves up at the top of the table so you can't really complain," the 24-year-old told Wolves' official website.
"We've not been at our best and we're still up there at the top of the table, so it's up to us what we can do from now on to improve.
"If we keep playing like we did in the second half on Saturday (in a 2-0 win over Sheffield United), we'll have a big chance of being up there at the end of the season.
"Points-wise it's not that bad at the moment, in terms of performances though, we know ourselves we can improve.
"But we do keep picking up the points and that's all that really matters at the end of the day."