Alright we all know that the Citadel upgrades are another layer unto themselves. What i do find though is that some of the more expensive ones can really cripple a player who is more intent on teamplaying than saving up for an artifiact. A few times i've had enough gold for an artifact and really wanted it but instead dumped huge amounts of gold into an aspect of the citadel purely for my team to utilise it.

What i think would be an absolutely awesome way of taking the burden off a single player in regards to Citadel upgrades is allowing an option beside each purchase to choose how much you want to put towards it.

For example(and apologies i am at work and have no specific price lists in front of me)

Say buying Catapultsaurus is 6000 - beside it you can choose to pay 2000 towards the 6000 cost. This would be visible beside the upgrade.

This then allows anotehr teammate to pick up the remaining 4000, or themself drop 2000, so the third guy finishes off the purchase at 2000 and the upgrade is bought.

This way you could do things like - early game, the tower health or dmg upgrades @ 500g - depending on what you like to buy first, you could perhaps buy an early item then drop the remainder of your gold - 150ish or something onto one of them, making it cheaper for the next teammate etc.

I dont think this would be overly complicated and would be a perfect way to further split the costs of upgrades across teammates in an intuitive way. I don't think anyone likes to be spending all their hard won gold knowing their teammates are being selfish and ignoring the citadel in favour of bettering themselves.

Alternative to this, it would be good to see a players name assigned to an upgrade when purchased so its crystal clear whose pulling their weight. Sure i agree that artifacts on certain classes can make or break the game, but the citadel is likewise highly important and should be shared across all team members. (2c)