Well I like big knives (8-9" blade) and can use them for just about anything that a small knife can be used and for lots of things a little knife can't be used for. In period bigger knives were still being built even in the latter half of the 1800's so there was definitely a market for them - these included not only Bowie types but the most common knife of the era the cheap butcher as made by Russell and others and widley used by Indians and frontiersmen. These were often in the 7-9" length with a thickness of just under 3/32" - original period knives, even bigger ones such as Bowies, were seldom as thick as many modern makers build them - the average thickness being no more than 3/32" at the ricasso area with the blade being properly distal tapered for thickness from hilt to tip - modern makers on the other hand far too often make replicas with blades of 1/4" and more - yes some period blades were that thick and even thicker, but the vast majority weren't even with blades in the 8-10" length
and as noted above one can carry/use different knifes for different purposes including a more or less dedicated fighting knife - not everyone was a camp cook
As for carrying a big knife being a problem? maybe that's due to so many replicas being way too heavy. A good 8-9" bladed knife need not be over 7-10 oz max. Properly sheathed and worn regularly enough to get use to a knife of that size it is easily carried and seldom gets in the way (a mid-back carry as often used by the earlier mtn men is one option)
Here's an example of a knife with a 9" blade and an antler handle - entire knife weighs 6.5 oz (the beaded sheath weighs more than the knife - but even so the combo weighs less than a revolver for the era):
this is one of my personal knives - 9.5" blade with antler grip - weight is 8 oz:
and another 8.5 incher with sheath the whole package weighs just 12 oz's:
as for what's best? bottomline - carry/use what you feel comfortable with, but IMO to state categorically that item A is best or that big knives have little or no use and are hard/clumsy to carry is a personal opinion based on your needs and not some kind of absolute fact.....
BTW - Kukris were/are dedicated fighting knives as used by the Gurkhas - they often have a smaller knife included for normal usage, but even the larger knife is not that heavy or awkward to use for some every day chores. While I've never packed a kukri on a daily basis I have carried a bolo type machete of about the same size (13" blade) and weight daily on my belt when logging and it was never a problem. The chainsaw with a 3-5 foot bar on the other hand was not the easiest thing to pack.....