I have gone 1hander no shielder and did just as well as when I was using longsword, though not as well as miadao or heavy greatsword as 1hers are the fastest weapons in the game when used without a shield. Its has far more to do with footwork and good manual blocking then what weapon category it is as the bastard swords and the 1hers most used are roughly the same length, speed, and damage. Now the greatswords, cleavers, nodachi are significantly longer so manual blocking is less necessary, same thing with poleaxes (spamming from out of reach or backpedaling spamming far more accessible).
The whole point is that anyone can do well with any weapon if they know how to fight, so Paul, just because you and others did well with a longsword doesn't make it OP (maybe you are OP), by its very nature the bastardized swords 1h/2h swords are in the same category as many 1hers and not the very large 2hers and polearms that are so decidedly larger that they make sense to be 2 slots. Having only 1 2handed weapon and then 3 random polearms (maybe more) that are much longer be 1 slot is rather arbitrary and shapes it so that you see archers kiting without a melee weapon because there is no even generic selection like: practice sword, axe, iron mace, bastard sword, katana; to choose from, by the way all these weapons are 101 length or less other than practice sword which is equivalent to staff, a polearm with 128 length and is 1 slot.
Its the arbitrariness that makes the game feel less smooth when you see these longer polearms and longer 1hers taking up 1 slot and then the 2handers being singled out for only 1 weapon and it excludes the practice sword, basic axe and 95 length katana, of all things. The thing is I really am happy with the 2-slot weapon idea, it just feels a little erratic in its implementation when it comes to borderline weapons, please make it smoother with a clear reason. I was thinking 106 length 1h/2h sword was a good cutoff before swords jump 9 length or more as it makes sense that you wear soething on a hip and run with it in 1 hand for it to be 1 slot, but maybe 101 length bastard sword is a good cutoff and at the very least including the cheapest 3 2hers similar to polearms to at least offer some diversity. Thank you.