Aggro Loam can't beat combo because its clock is bad and it doesn't run enough disruption. To have enough space to fix those things, you'd have to take out the Loam engine, and then you're not playing Aggro Loam anymore.
But once you give up on wasting a lot of space to try to "fix" something that is inherently unfixable, I think Chalice starts looking pretty questionable. The card is a drag in the tempo matchups because having it in your deck keeps you from having a relevant early game - you're not playing enough cheap spells to slide under the disruption, so you end up needing to have a fast Chalice or you're just derping around, playing half a turn behind your opponent even when you went first. It's okay versus control because it keeps them from burying you in the mid-game with cheap card advantage spells, but I feel like Liliana does sort of the same thing these days. Running a real mana curve also means you can simply
do more in the mid-game, which lessens the chances of them being able to break your momentum with one or two key FoWs. The place where a Chalice would be most valuable are all-in combo decks (set to zero, it eats a lot of their important mana) or something like Sneak and Show where they're using cantrips to both set up their combo turn and hide important combo pieces from discard by leaving those cards on top of their library until they're ready to cast them. All-in combo is kind of a crapshoot for you anyway (see above), and I don't recall Sneak and Show being all that favorable regardless. Then again, I haven't played against the deck in years, so maybe things have changed.
Resolving a turn four Chalice against blue decks was also very hard, IIRC. You had to kind of just cross your fingers and go for it because playing around counters at that point in the game meant you'd never end up casting your Chalice. You'd cast a threat and they'd let it resolve because they could Brainstorm/Ponder to an answer, so you'd cast another threat just to be sure and they'd let it resolve again because ditto, so you'd figure the coast was clear to cast Chalice and then bam, the Force of Will your opponent was sitting on. Weaker opponents would just slam Force against the first scary card, but then you didn't need Chalice to beat weaker opponents - it just made them scoop faster. It's the same reason I hated DD against blue - reasonable competent blue players who knew what you were up to also knew that realistically there were maybe five cards in your main they
had to counter, so they could save Forces for those and use weaker counters on tempo plays or nudging themselves ahead a little bit. You had to just go for it and hope if you were even or behind because if you were far enough ahead that they had to counter your big threats then Chalice or DD were interchangeable with any of those threats as ways to force concessions.
I think a build that focuses on board control and uses Liliana and Thoughtseize or Inquisition to force your opponent into topdeck mode would be worth exploring. You could even board
Raven's Crime against control to reduce the value of long-term card advantage. They'd have to use cantrips to leave all the good cards on top of their libraries, which frees your hand somewhat in the short term to close out the game.
