I haven't played it long enough yet to have any suggestions for PT2. I'm sure after awhile I will.
I wanted to comment on the time alloted for the demo. I think it's too short. I know an hour is standard for a demo, but in this case I don't think it works. Unless you mess with your computer time while the plants grow, you really don't get to do much. Since it takes the plants over half of that hour to grow, people trying the game don't get much of a chance to try making seeds or buying improvements.
Don't get me wrong, I knew I wanted it BEFORE I tried it, but people who are new to LDW may be turned off by not being able to do much with the demo. So I suggest a longer demo time for PT2.

Marcey