1. If you have 32 ETH would you run your own validator or stake it on a pool with others?
Depends, if i have Good connection, Low Electricity, 32 ETH and Spare time i will run my own validator but if not i will stake it on the other pools, Small Fee but less maintenance is better i suppose
2. What are the penalties if the validator is offline for 2-5 days?
Not really sure but i read somewhere our eth will be bleed,miss or gone slowly (?)
3. What's the rate of return difference between solo staking and pool staking?
Solo = You controlling your and get full payment without any fee (Only maintenance)
Pool = Pool Fee
Not really sure since i'm not fully understand Ethereum 2.0 Concept for now but the simple logic is, Solo = Much better?