I can tell you , as a provider, that I have dealt with this with young kids like your and it is pretty difficult. Kids are resilient and all that, but this young stability and security in a routine reassures them. I recommend finding a full time provider, or 2nd best, have someone who comes to your house the other 2 days. At least then hes in his home, etc. A notch down from being home with a parent those days..at least the "at home" part is in place.
For older kids..3.5+ who do preschool a few days a week then maybe a more laid back daycare/playschool environment, thats easier for most, but not all kids, as they are older and can get a grasp on different rules and routines. 20 mos they want sameness, etc.
Best of luck! I know for parents that has to be one of the most difficult things..finding a perfect stranger to care for their precious child. I do what I can to ease that for my clients.