Oh dear, I forgot -new unit syndrome

You know what I mean...the dreaded under-performance of freshly raised/painted units  on the table in their first battle. Outsmarted, out marched, out shot and out melee'd by the wily veterans of the wool felt and plastic buildings.

Now this sort of problem typically resolves around one or two units going awry in a game.

Then there are my Swedes....at last count, twelve battalions, most of my Perry miniatures have not rolled a volley in anger, nor gone after an enemy with 'cold steel.' There are also seven more in the pipeline! Hmmm, must rectify the problem.

 I  can throw my three Jager regiments at my Russians in Chosen Men scenarios, the rest of the army blooded against my ever faithful white coated French in a couple PK or Black Powder games. 

I do have some Danes who also fresh faced, be in some Chosen Men games as loyal opposition.

Or, should I just let Scandia's to be written history be the crucible for all these and the next 7 battalions to paint? 

These sound like first world problems, eh?  Any other way around this?