The rule is that the tie width needs to match the lapel width of whatever jacket you pair it with. To do that of course you need to know the correct way to measure lapel width. There's no reason why you can't do it the other way round i.e. match the jacket to go with a tie you particularly want to wear - the important thing is that the tie width and lapel width are more are less equal (I'm sure 1/4" difference between the 2 doesn't matter).

If you're wearing a tie with no jacket then wear whatever the hell width you like. As for 3.5" being too much - not at all, it's a nice width.

Disclaimer: I don't do the Boom Years Ivy thing, I love to look at it in the old ads etc. but I much prefer the traditional look of the 1970s-1980s, so I'm a bit more comfortable with wider ties than someone who is oriented more towards Take Ivy rather than the OPH.

My slimmest ties are 3", and my widest tie is a J. Press paisley that comes in at 4 1/4". Most of my ties are between 3.5" and 4". Most of my lapels clock in between 3.5" and 4", with only one (on a B2 University Shop blazer) coming in at more than 4". Therefore, I have trouble pulling off a 3" tie but no real problems with ties at 4" or a little wider. I prefer 3.5" ties for purely aesthetic reasons, but as I buy all my ties for about $5 used, I buy based on colors and patterns and don't concern myself too much with width - also because I know the makers I like, Brooks Brothers/Rooster/J. Press/Lands End/Jos A. Bank/etc., weren't making crazy wide ties anyway.

You aren't going to look like a movie mobster wearing a 3.5" tie, this was the classic width for lapels and ties at Brooks.

not counting narrow knit ties with square ends, of which I have a few (I liked the wool ones best, better than silk, cotton, etc.), nearly all my ties are 3 to 3.25 inches wide at their widest point, I might have one or two that are 2.75 but that's it ......

I bought almost all of them myself years ago, new, at Press/Brooks/Andover, long before eBay and the internet, I needed the ties for work .......

all are from England or the USA

still have the vast majority of them, though naturally there have been a few casualties over the past four decades ... lunchtime casualties ... never lost an all-time fave though

I'm from the OPH generation '78-'82, and to my eye narrow ties are either a bit '50s/'60s uptight or self-consciously late '70 New Wave, either way the skinny tie is not what I have worn

so, for regular neckties, 3 to 3¼ inches, and for square-end knit ties 2 to 2¼ inches

measured four just now, a navy/red Press animal kingdom collection emblematic from the '87 era (3.1"), a striped Brooks Brothers Makers #2 rep woven in England (3"), a Press wool/mohair striped knit square-end (2"), and an English-made wool knit square-end (2¼ ") 

3½ inches is a bit on the wide side, do not exceed it

what is the proper width for The Clarney?

Skinny ties I do not like, even on Evans and chums photographed at the Village Vanguard circa 1961. 
Ties once sold (possibly now Sold Out) at Chiltern Street were often too colourful for my simple tastes. 
I parted with the majority of my 'collection' back in early 2012.
Now - stone me - finding anything at the right width, made of silk, wool, cotton, in England, Italy, the USA is proving painful.
Any names I should be looking for?