Jimmy Smith put the home side in front after 10 minutes but Kirk Millar levelled 50 seconds into the second half to earn Oldham a 1-1 draw and a deserved point at Brisbane Road.
Slade said: "We've finished seventh in the league, which was the best we could do before the game started so we have to be very satisfied with that.
"We didn't want to get beaten, we wanted to finish seventh and we've achieved that, but I was disappointed with the goal just after half-time and the way we played for the first 10 minutes. But apart from that, we were fine.
"We got ourselves a goal and we might have scored a second when Coxy (Dean Cox) hit the woodwork. But we played against an Oldham side that were energetic and that worked extremely hard."
The O's boss added: "We will be spending a considerable amount of money on our pitch during the summer because it has been difficult. It was very bobbly today. Oldham came and pressed us and on a surface like that and they made it really difficult for us at times, so all credit to them.
"It's going to be an interesting and intriguing summer and we'll be trying to attract the best players that become available to the football club. We have a nucleus of players here for next season, certainly defensively, and we want to strengthen the squad."