Okay I’ll step up to the plate on this one.
First welcome to the forums.
Second, your tree trunk looks okay, I would show it off from different angles. Maybe think about combining the two projects into one.
Okay Now third: your alien thing, though simple, needs adjustment.
It’s a fresh water alien? Did you do research on aquatic fresh water life. They tend to share certain quailities: dark neutral color tones i.e: earth and stone tones. They’re either completely smooth or extremely bumpy. They have limited patterns.
Your alien is missing all of that. Including anything signifying him aquatic.
Either change the name or the concept.
Also though I really encourage fun with this software, I do think you should do studies of these things.
And don’t rush the community you’ll get comments in time:)
happy zbrushing.