Nobody uses combo fields. I can hear you out there. "but wait dude, my rotation constantly blasts fire fields." or, "I blast in water fields to save my dying group all the time" which may be true. But as soon as you get too many players in one spot, all the fields you lay down, get overwritten by everyone else.
Wanted burning bolts? Probably got cleansing bolts. Thanks firebrand. Wanted to blast a heal? Probably did AoE Weakness. Thanks scourge.
So... How do we deal with the fact that, in open world groups, combo fields can work. (a few guys doing quests and zones while coordinating.) in 5 man group content (and by that I mean fractals, let's not kid.) your fields will get overridden. Unless you coordinate with your party to choose classes whose combo's play nice.... Which is a bad idea, because you'd much rather have classes that can produce the boons and conditions you want without needing combo fields at all. Which you can easily do between the PoF release and HoT.
So, my proposal?
When you combo in your own field, overlapped by another player's field... Two things happen, first you always combo in your own field. Secondly you have a 20% chance to ALSO combo in the newest unowned field.
So, the effects of the change would be that doing combos with your own fields can be relied upon, even in WvW and raids. Yet, group play is still encouraged. If a group wants to declare, 'blast water fields on the zerg' it will only take a moment before everyone is dropping thier own water field they know they can blast in. If there are other folks who continue, against the zerg commander's wishes, to blast thier own fire fields, this allows them to do so, while still occasionally succeeding in helping the group by accident. (20% of the time) All while allowing wise players to NOT put out a combo field of thier own, knowing that it increases thier chance of combing with someone else's field to 100%. And allowing this players who did put out a water field, to continue blasting might even if by accident.
I don't know if this is extreme to say, but I don't think a wider variety of combo effects +20% net total number would break raids, or WvW. Boons have a cap. Condis from combos are mostly disabling or hard to aim.
Auras... Require a subtly different action in order to maintain the 1 aura at a time mechanism. Otherwise a leap could produce a fire and ice aura simultaneously. So, if the 20% chance triggers as you leap through both your own, and someone else's field, you should do a single whirl, or blast at the other player's field. (50% chance for either one)
This maintains one aura at a time, and makes the leap slightly unpredictable in the way it combo's with multiple fields, thus reducing the idea that folks might build combos where a player uses a long leap through someone else's multi field. (like berserker's longbow f1)
I would also toy with adding an option, either in the options menu, or on the UI that allows you to set yourself to combo your own fields as primary, or to combo with others fields as primary. So that players can choose whether they want thier combo finishers to work selfishly, or not.
What do you guys think? Cool? Or totally break the game? Is there a better way to make combo fields feel as rewarding as they did back at release?