When I was learning to fly an old and wise flying instructor told me he had a device for deciding if weather was suitable for single engine IFR. It was a blue card with a hole in the middle. If, when held up to the sky, the hole and the card matched in colour it was OK!
On a serious note I have had an engine failure in IMC in a single had it not been for a reasonable (1500') cloudbase a crash would have probably been the result.
It is a consideration.