if it helps: I’m new to this game too and 5’11" and 200lb with clothes. I have rafted with my 26 lb bike and a small ruck sack on the Yak (which fits me perfectly) and buoyancy was no issue. I wouldnt want the larger one, I dont think…its a nice fit to have my feet braced against the bow tube.
I have a cruiser deck and no cargo zip - its gritty here in scotland and i was concerned re zip contamination leading to some air loss and didnt need the stowage as low in the boat as i’m not aiming (yet) for white water…just Loch crossing and some mellow river floating…
Im 5’8" and 125 pounds. I have an alpacka scout which i fit in and its relatively comfortable. I also have a ww decked yak and it fits just right. I would personally size up to the llama if i were you. Once you bury yourself under a skirt its alot tighter, almost claustrophobic really. On on long days its nice to be able to stretch out a little. Also of you can afford a deck, any deck, get one. Its nice for rain, chop on lakes, paddle splash and of course white water. Also ot can make a nice table for fishing gear when your switching out lures.
I got an explorer 42 for solo river fishing with my pup if I feel like bringing her… otherwise I’m hoping the Alpacka description of it being the easiest big raft to solo paddle is true, If I can rig something to make it stable in up to class 2. If you haven’t made a decision I’ll let you know how my explorer 42 fairs.