Actually, it wouldn't. In 1826, Congress abolished property qualifications for federal elections, and in 1841 (or 1846, senior moment here), Congress set the date for federal elections to the date we still use today.
On the issue of federal elections, Congress has complete control of the process, and no amendment is necessary.
For your proposed changes to the Electoral College, that's another story. You're right. The Constitution gives the state legislatures plenary authority to determine how electoral votes are to be handled, and your proposed change would require an amendment.
This is an interesting thread:
https://www.freerepublic.com/focus/f-news/3763102/posts
“Records show Clinton dined with Epstein in 1995, predating public timeline”
Lots of info in the comments...