It depends on where you set Witness in the line-up. It still has Christmas decorations up, so technically it should be sometime within the week of Christmas 1993 (either before or after).
I've been told that Witness was originally supposed to air earlier (pre-ASU), so I've usually put it after Man of Steel Bars (which is set in Nov. '93). I realized recently though, if you take a look at the calender that Rourke points at in HiM (or you can take my word for it, since I've already done the research), the airdate (12/12/93) is close to when the episode was set (or when Lois and Clark are in the Honeymoon Suite at the Lexor. IOW, that's a Dec. 1993 calender). So, you could move Witness directly before ASU (making the whole Nightfall incident take place in January). Keeping Witness in January (per it's 1/9/94 airdate) seems unlikely because of the lack of Christmas decor in ASU and because there is Christmas decor in Witness.
"Ides" from "Ides of Metropolis" refers to the 15th of the month, since Vatman takes place on Perry's birthday (per Jimmy leafing through Perry's desk calender, we know is on March 17th), you could set IoM in mid-Feb., but that would mean Foundling happened at the end of Feb 1994 and Rival at the beginning of March.
Then you could safely assume FlyHard takes place in April and BatP in May (or late April).
I've always assumed that HoL wedding took place in June, because I could see Luthor wanting a June wedding as it was usually his desire to have himself appear traditional, but as far as I know it isn't stated as such in the episode. Being that Lois requested that they wait until their wedding night to consummate their relationship, I could see Luthor wanting to hurry and have the wedding ASAP.
Hope that helps and I didn't leave you