The trials are totally doable without having an alpha slotted. I do them all the time.
Edit: Unintentional giggity.
And you can craft alpha powers using the trials you don't have to do TFs.
@Mental Maden @Maden Mental
"....you are now tackle free for life."-ShoNuff
I'd imagine it might depend a bit on your server, but my experiences indicate that raids are still conducted on a regular enough basis to get you what you'd want (and the new Underground trial is quite excellent for getting raw material and Incarnate XP), and high level TFs are still run about as often as has been normal (less than right after i19 hit, perhaps, but at least equivalent to i18 and before). And WTFs are likewise remarkably easy to get onto.
I'd recommend checking your server's global channels, and just keeping in mind that there's almost no difference between leading and joining a group as far as Task Forces and Trials are concerned, really.
Ah Fantastic, that pleases me greatly, I was hoping it would be easy to jump in and get back to work on the incarnate abilities. Thanks for helping. 
I unfortunately didnt get a lot of playtime since Issue 18 and while i have the alpha slot unlocked and gone one step up the tree I have not had had the opportunity to do much with the Incarnate stuff and so I know Im a little behind the curve. How hard is it to get caught up now? I see everyone doing the incarnate trials but are folks still doing the task forces that drop the other mats to help unlock the other abilities to get farther up the chain? Can one even do the trials with just the alpha slot unlocked and still contribute? How does one get caught up at this point? Thankies and Happy Pummeling!