Probably 122 You have the Ring Fight of the Year at 122 in the years 2000, 2006, 2007, & 2008 plus the round of the year in each of those years. You also have plenty of bonus classics as well: Larios vs. Vasquez II, Vasquez vs. Jhonny Gonzalez, Gomez vs. Pintor, Morales vs. Zaragoza etc. The classic weight classes like welterweight and middleweight obviously have a richer history by miles but in terms of sheer ultra violence (as well as a consistently high level of competition) 122 is already catching up to the other weights in terms of the blood spilled over its history.
Light-Heavyweight. Perfect mix of size and power allied with speed and athleticism when you're talking about the best 175 operators. Peaked between the reigns of Foster and Spinks in terms of excitement, great fights and styles match ups.
Heavyweight and Middleweight, though particularly heavyweight Boxing lives and dies by the heavyweight division, and imo, it has the most interesting history. Usually because of the importance placed on it
I can enjoy any weight classes but to me nothing better thant two skillfulls fighters going at it from 105 to 135.
Now for me, it is about the fighter fighting. Not the weight. AND, I watch this sport for the unrestrained violence and blood, leading to honor. You can keep yr nonpuncher slap fights. We need pain and overcoming the pain and damage, not little slappers or defensive sleep inducers.
I see your point. I think the top guys fighting will always make great fights somehow and create great fighters. There are possible great fighters out there who probably never became great because they never fought the top guys to make a great fights. They were never tested, but one guy tested is another guy coming out the winner. These weight tournaments are good because they create a situation where the best are tested and improve.
Right now? Crusier. The last few years have been absolutely the best since it's inception. All time? Ooh...