They need an upgrade option for the other +gold items.

Super philosopher's stone, hooooo~

If you're playing a nuke mage (Annie, Viegar, etc). You'll be much better off not investing. Odd's are a normal item will allow you to kill a hero with your initial nuke. Screwing that up, often means your death. 300 gold kill > kale's pick.

+5 gold items and especially the pick are really great items if...

if you know you will not win midgame, but lategame
if you get them early enough (I get some picks usually after catalyst and boots)
if you get them before the game enters the ganking and stalling phase.

People are always complaing about the +5 items that they are a waste of gold and you could get better stuff.
Yes they are, if you can not utilise the stats on them.

Philosopher's is bad! No doubt here!
Heart, Pick and Blade are good items, if you need health/armor, ap or crit.

If you can get some of those before you enter gankmode you may enter a win/win situation.

Usually when both groups are teaming up the game begins to stall.
You won't get money from creepkills or champion kills when standing in front of your enemies and their towers while trying to get an opening.(Or the other way around: you are defending.)
This should start around 10-20min I guess.

At this point time will be on your side.
Your enemies won't be able to farm either and the money will tick for you.

To sum everything up:

+5 Gold Items are good, if you are willed to trade your midgame for the lategame!

You dont need Philo stone nor Kage's ****py Pick (at least on the 3 champs you mentioned). Buy Saphire+potions or Ruby. Make catalist at 1st trip to base. Profit.

As for my experiecne - whenever I saw someone stacking this ****, they were a losing team 90%, with the exception of my friend playing Eve (though I already told him to get better items).

P.S. Heart Of Gold is actually good item. It gives armor/HP. Saw it in higher ELO games on many tanks. Avarice good on Pirate and new Tryndamere, they utilize cheap +crit chance very good. Kage's is a **** - 25 AP wont make your day, even if you have good AP ratios. Casters are fragile and need mana, catalist is best way to go, while gankers such as Eve will benefit more from fast Sheen/ 2nd boots. Philo stone - Chalice/Catalist > philo stone all day long.