Something I have been attempting to isolate is malty sweet and caramel sweet.
I have been mainly brewing without any crystal malts to help define the difference that mash temps have on sweetness just from base malts. Pushing the higher temps, it turns to a cloying level along the lines of cake icing. Going with a lower mash temp and adding crystal malt, the sweetness is not so cloying and more dimensional.
In general I mash for a drier beer (149-152 degrees) and favor sweetness from crystal malt not going over 10% of grain bill. Crystal 40 is my overall sweeting agent and the darker lovibonds are used to take the sweetness in different directions.
Now I am looking for input from others on their approach.