Since I asked the question, I should probably add in my two cents.
Actually, you all brought up good points, across the board.
Starting with Rizz, it's true that the Sunday tradition started with Constantine, right down to the fact that once the emperor said "Be a Christian and do it this way"...ya kinda just did it or became a roadside spectacle.
FYI, the reason Constantine instituted the Sunday stuff is kinda interesting. The reigning religion in the empire, up til this point, was the worship of...(drum roll), the sun god (I can't remember his roman name) which was named Christos in the region over kinda near Egypt. In order to include as many people as was possible into the new state religion, Constantine outlawed Judaism and adapted the sungod worship to create a new "christianity."
Anyhow...it was Jesus that said "man was not made for the Sabbath, but the sabbath was made for man." In the "law," the commandment says "keep my Sabbath holy." which literally means..."continue to set apart those days that I have instituted as days of rest from your labors."
We've kinda made it out like the sabbath is a bad thing, all legalistic, and us not being able to do the dishes or whatever. But, before the Pharisees had their way with God's instructions..the sabbath was party day. It was a day when you got to chill with your people and discuss how God'd been working and teaching and all. It was..and is...cool.
That said, no place in scripture does it say that worshipping on Sunday is bad. In fact, the early church was said to continue in worship and teaching of the Word and the whole nine every day of the week.
I like that idea.