Fiddles: be absolutely sure your set up is correct for the type of music you want to play. This includes nut height, end of fingerboard height, bridge height,and bridge arc shape. Check out different kinds/types of strings to get the sound you want. Steels are very bright and brassy, "cored" are more mellow. "E" strings are a booger to get the right sound on, so check out lots, some of us use a different brand of E than the other 3.
Spend more on the bow than the fiddle if you have to. If the bow does not have a natural action, it won't matter if you have the fiddle to end all fiddles. Good bows start at about $200, classical type soloist bows will go for upwards of $10,000!
To break in any acoustic instrument, try hanging it in front of a speaker in a way that the vibrating body of the instrument touches NOTHING, and play music through the speaker. Can reduce Break in time to almost nothing.