As a Thistle fan, I've had the benefit of watching Stephen O'Donnell for ten years now. He has not achieved his current status as Scotland's first choice RB/RWB through being a limited player. One other factor to bear in mind - what position did the current national team manager play? Not only that, the current manager was his club manager for two seasons or more. All valid considerations.
Nathan Patterson may well go on to become Scotland's best RB/RWB since Danny McGrain - and I sincerely believe he could be that good if he shapes up defensively - but not at this moment and probably not for a year or so.