I'm an NJ scratcher. I can't say if NJ is better or worse than other states, because the only other state I play in is NY. In NY, the prizes are higher for tickets $5 and up, e.g the typical top prize for a $5 ticket is $1 million, and in NJ it's $150k. However, in NY, you get paid over 20 years; in NJ, it's all at once (except for the Win For Life games).
I look at the NJ lottery web site and read the details on the various scratchers. You can learn a lot this way and make more informed decisions based on what you're looking for in a scratcher. I prefer games that give you better odds at a mid-level prize, even if that means a lower top prize. I know the odds of me winning the top prize are so remote, it probaby never will happen. So, I'd rather get a better shot at $100 or $500. In this regard, "Lucky Gift" is a good $5 ticket. The top prize is "only" $25k (compared with $150k for a typical $5 NJ scratcher), but the odds of winning $100 are MUCH better than other games. The Odds of winning $100 are actually better than winning $20 in this game.
"Big Money Spectacular" is a good $2 scratcher. The payout is 70% (compared with 65% for other $2 games).
It shouldn't make a difference where you buy your tickets (from a real person or from a machine). I tend to buy from a person because that's what's closest to where I live. But, I do buy from a supermarket vending machine if I am there. I won $100 on Big Money Spectacular from a vending machine.
Good Luck!