Just a small thought, a small wish.

The BF Sword is one of the most expensive single items in the game. You have to commit to saving up for one for quite a while and the return is all at the end.

My suggestion is simple.

Long Sword x 3 (~1200ish) builds to BF Sword (For the remainder amount)
Total price is exactly the same as current BF Sword.

Just makes the increase to the final AD amount a bit more gradual so you're not going for so long without even a little added damage. It'd help characters like Tryndamere early on who really need a BF Sword item and have to spend so long with little AD boost until they can get it.

Changes nothing in the long run, just makes it less of a pain.

I agree. AP classes can build top end gear from tomes and blasting wands in the interim. Melee doesn't have a lot of in-between items short of the new Ghostblade and things like Zeal-->Phantom Dancer.

I disagree. The point of a BF Sword is that you sacrifice the interim items in order to get it. If you want early-game AD, get a Brutalizer (which, IMO, is extremely good for its cost). If you want to rush a power item, that's why BF Sword is such an expensive one-shot item.

If BF Sword were built up from lower damage items, it would reduce the timing disadvantage that you're supposed to be putting yourself into for a stronger later-game. It's balanced the way it is because if you commit to going for BF Sword, you'd better be able to farm it up quick, otherwise you're just going to feed.

I'd have to check (and I don't have the time atm) but I think BF Sword is at least twice as expensive as the next base item in the game (except maybe 1-2 of the more expensive combine costs). Yes, it is a huge damage boost, but the cost is way out of wack compared to (almost) everything else (Trinity Force the second most expensive total cost is made up entirely of components/combines that cost ~400-500, allowing you to have something in the interm while you farm it up)

The main problem as I see it is that BF sword gives the same ratio of gold:damage as a pickaxe, which makes no sense as other items have a better value:stat ratio as they get more expensive.

This is a terribly weak argument. You are basically saying 'It's that way because it should be' and not providing any compelling reasons why.

What does this 'timing disadvantage' accomplish? Nothing. When you go for something like a Brutalizer, you're getting it because of the bonuses or to build it into something. That piddly 25 AD isn't why you're there.

What does making the BF Sword build off of Long Swords accomplish? In my opinion, a lot.

You get a more gradual increase, making the cost a little easier to bear and giving a more immediate return for your money.

It encourages more non-linear building; you get a long sword, then next time you reach the shop, you have more options to devote that long sword to, whereas if you're going for a BF Sword right now, you have one option: Don't spend anything.

I also wouldn't be averse to the pickaxe, blasting wand and crit cloak getting a similar treatment, but their cost isn't nearly as severe so it's not quite as bad.

It's a port of Sacred Relic from DotA. It's intentional.

Incorrect, sir.

Long sword is 10 dmg for 415 gold, or 41.5 gold per damage.
Pickaxe is 25 dmg for 975 gold, or 39 gold per damage.
BF Sword is 50 damage for 1850 gold, or 37 gold per damage.

You get 'more bang for the buck' buy buying a BF sword.

5 long swords = 50 dmg = 2075 gold (5*415)
2 pickaxes = 50 dmg = 1950 gold (2*975)
1 bf sword = 50 dmg = 1850 gold

BFSword is the best investment for damage, and it only takes one item slot. Well worth the 'wait'.

This isn't DotA. Ideally, LoL should be surpassing DotA's limitations, not restricting itself to them 'just cause'.

This is more a general response than targeted at you:

I don't think building into a BF Sword, as opposed to having to save up to buy it outright, hurts the BF Sword or any other item. The end result is exactly the same: you spend 1850 on 50 attack damage and you need this item to build into some of the most absolutely necessary AD items for a DPS.

The only change is that you now make the investment in pieces instead of having to save your money specifically to buy it all at once. This makes building AD less of a pain and improves certain characters' earlygames without actually changing anything about them at all.