How many paintings do you have lying around gathering dust? Is there any chance of them being used for exhibitions? You might be dissatisfied with the end result. Something is missing - just doesn't have any 'umphh'.
Why not haul one or two out and have a go at collage.
Repaint a watercolour in acrylics. Darken some of the darks with a colour you would never use normally.
Lighten some of the lights to make them come alive.
Choose some adventurous light colours that really glow. Bright yellows and greens.
It is only a piece of paper or a canvas lying dolefully in a cupboard or drawer.
Make the experiment fun and enjoy yourself. Free yourself from the necessity to have everything perfect. Use a big brush or a painting knife and let all that built up frustration and creativity have its way.
I would love to know how you get on. Please share.