Think the bigger balance change for 18/27 archers is that they will be able to go 18/24 and more or less maintain the same WPF, freeing up 7 skill points.
High conversion builds are never the way to go for maximum effectiveness, instead they're what you do when you choose to specialize in something, and that's what the build is all about. For a higher level character, 18/27 is the same as 18/24 is to a level 30. This probably won't happen though, because the status quo would have been changed. Another way to put it, is that a build's perceived effectiveness(18/27) isn't only about how well it does against other classes, but how well it does in comparison to other similar builds, primarily within its own weapon class(an 18/24 archer build underperforms an 18/27 with a bow, yet also underperforms an 18/21 as a hybrid build and thus outperforms it with a bow). And it's this perceived effectiveness, not actual effectiveness, that we base our decisions upon.
Any way to address this?
Yes, but I'm not convinced we should be catering to certain types of hybrids. Does hybridization bring variety to crpg? Yes, absolutely. Should variety be the overwhelming priority and focus in such a way that we might occasionally forsake other gameplay aspects? No. I love variety and I love customization(no one who has taken a look at the item patches this year can honestly state otherwise), but all things are best in moderation. Do I have a problem with double/triple melee hybrids? No. Do I have a problem with melee+ranged/cav hybrids? Yes, these are what worry me. I don't want to nerf ranged or cav, that would be far too broad of an approach with a wide range of consequences.
My issue, is that a 2:1 or 3:1 ranged:melee wpf split is better for gameplay than a 1:1 is. A 1:1 split doesn't have to make nearly as much of a sacrifice as a 3:1 does. Because of this, we have the current status quo which is too inviting to players to do certain melee/ranged hybrid builds, particularly but not limited to, those that involve crossbows. What I'd rather see done, is doing things like rebalancing the crossbow back to how it was pre-nerf, and changing hybrids so that it's less effective for those 1:1 ratio splits, and more effective for the dedicated/3:1 guys. Unfortunately, the current wpf status quo keeps us from doing this and thus limits the viable options a dedicated(specialized) player has to choose from.
Lastly, for melee hybrids the following would be ideal, although no promises are being made. This falls well outside of my realm and requires overlords.
"<Shik> so tydeus
<Shik> wpf in any melee category having partial effect on other melee categories y/n
<Tydeus> yes.
<Shik> the only difficulty is coming up with the right sort of maths
<Shik> to make it make sense
<Shik> probably easier just to have combined melee wpf
"
tldr; this
is the tldr version.