The Rebels had harboured hopes of squeezing into the playoffs after the Auckland Blues' victory over the Otago Highlanders but the defeat for Kevin Foote's injury-hit side brought a close to a frustrating campaign.
"We've got a platform there now where we know how we want to play, what that looks like and what it takes to win," said Wilkin.
"There's some lessons that we learned this year and what we need to do better to get those wins. It's a learning experience for a lot of guys.
"The group is very strong and we'll keep working towards next year and I think we'll be a lot better for it."
The loss to the Brumbies was the Rebels' 10th defeat from 14 games this season and head coach Foote was unhappy that his team had been unable to keep their Super Rugby campaign alive for another week.
"It's very disappointing," he said. "It's not where we set our goals to be and I think we played some really good rugby this year.
"It's a really nice group to coach and I feel really disappointed that it's come to an end.
"Sometimes you get to these points of the season and the group's a bit drifted or they're not all committed, but I never felt like that with this group."
