If a magazine is published regularly and we know the date of the first issue, then it should be a straightforward process to add it to the database. Unfortunately game magazines don't always start out as regular publications. If we just guess or add issues with incomplete data, then we can wind up with problems like we just had with Game Player's or like we do now with Tips & Tricks, where the numbering in the database is off from the official numbering and it looks like we have database entries for issues that may not even exist.
The official numbering can be confusingly irregular anyway, so maybe these kinds of challenges are unavoidable and are part of the research process. It should be straightforward enough to add Weekly Famitsu, because by the time it was officially published with that name it had a regular weekly schedule and has maintained that schedule ever since. The English Wikipedia says Weekly Famitsu started with issue 369 but the Japanese page says 368. I'm more inclined to believe the Japanese page, but if it becomes a problem later down the road than it should be easy enough to fix.
So, Phillyman, in theory you should be able to start Weekly Famitsu with issue 368 dated January 5th 1996 and increment each entry by seven days all the way to today and it should hold up. That's approaching a thousand database entries, though, and that's not even including the previous decade's 367 issues when it was known under different names or the many Famitsu spinoffs or monthly Famitsu.
You could probably also create entries for when it was known as "Weekly Famicom News" which started with issue 135 dated July 19th 1991 and ran until issue 367 before it was changed to "Weekly Famitsu" with 368. If you look at the Wikipedia pages again you'll find contradictory information on when exactly these name changes happened and the dates of the issues. I think some of that confusion comes from the date printed on the issue and the date when the issue actually hit newsstands.
I've come up with these values with the issue numbers stated on Japanese Wikipedia and the dates corresponding the seven-day increments that match up with the issues I have in my possession. So, I can look at issue 455 dated Sep 5 1997 on cover which I just scanned and tell you that the issue 623 was 168 weeks later and was dated Nov 24 2000 which matches up exactly. So issue 135 should have been dated July 19th 1991 and so on.