Don't pick small topics, do you?
Okay, general rules of thumb:
Whether an aromatic will cellar well depends on the type of aromatic. For the most part, the toppings can fade over time.
Virginias can age for decades before heading south. Depending on the leaf, they may become sweeter, more complex and deeper in flavor. Generally, the most pronounced portion of the aging process takes place during the first 5 years. The rest is incremental. That's according to Greg Pease and I have no reason to doubt him. I've smoked some 40+ year old leaf that was spectacular, and much more that wasn't.
Burleys are the aging king. I've sampled very old blends where the only clear component left that hadn't turned into zombie vomit was the burley. Some write that burleys don't actually age at all and don't change over time, but I don't believe that. The change is subtler, but I detect a greater nuttiness to the flavor.
Latakia fades over time. There is a difference of opinion regarding how long it remains pungent. My experience is that Lat holds most of its strength for the first 10-15 years and starts to fade, a term which some like to replace with the term "soften", such that it is pretty much gone after 25 to 30 years. A lot of people like the flavor of "softened" latakia over fresh. There are always exceptions, but this is kind of a generalized timeline.
Oriental leaf tends to have a long life, much like Virginia. You may find in older tins that the Latakia has given way to the Oriental tobaccos.
Many believe that tobacco is best aged in it's original tin. Others believe that the only way to store for long term aging - 10 years and up - is to seal in mason jars. What my experience tells me is that most tins are fine for several years - maybe as long as 10, and some survive for decades, but most are leaking from the moment they leave the factory. In particular, the flat square and rectangular tins are most prone to failing. If you fill a plastic tub with tins and seal it, then open the tin a few weeks later, you will smell tobacco from the "sealed" tins. Put your English/Balkan/Oriental tins in a sealed tub for several weeks and you will smell the Latakia and Orientals when you pop the top of that tub. Fill a tub with Virginia, VaPer blends and seal it, give it a few weeks and open it and you will smell Virginia and/or Perique. Over time that very slow leak will fill the vacuum in the tin, causing the pressure to equalize, the seal to fail, and the contents to dry out. The percentages for failure get higher and higher as the years pass. Many either jar the contents of the tins, or seal the tins in heavy gauge food grade Mylar that has been heat sealed. Keep in mind that these tins were never designed to survive for year after year before being opened. It's irrational to believe otherwise.
Even if you choose to jar everything, you may need to check that lid every 5 years of so. They're not guaranteed to last more than 18 months.
What would I choose to cellar? Whatever I enjoy smoking. I'm aging FVF, SJF, 2015, 2010, 5100, Haddo's Delight and a bunch of other blends. Virginias, VaPers, VaperBurs, etc should be good for years. I wish I'd cellared the VaPer version of Bells Three Nuns. BS-LBF really improves with a minimum of 4 years on it. English blends will change over time as the Latakia fades and the Orientals become more prominent in the blend.
I'm in the middle of jarring up my old GL Pease blends because the C&D tinned canisters are failing. Just found a tin of GL Pease Renaissance that's dry as dust and am rehydrating it. My newer tins from other makers are being sealed in Mylar for now. It's a process.
But here's something to consider, the idea that aging "improves" the flavors of tobacco. Aging certainly changes the flavors of a blend as the components alter over time and as they meld so that one experiences a more unified flavor and less variation from the individual component leaf. Whether that change is an improvement is up to the taste of the individual smoker.
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