Is a 70 lb archery bow draw weight any better than a 60 lb draw weight?

no! it is more important that the draw weight be comfortable to you. however if you use a 70 pound draw, the arrow will travel faster, straighter and with more force(better penetration).

It depends upon your ability to draw & hold the bow, and what you plan to hunt with it.

If you can hold at full draw for 8-10 seconds without fatigue or shaking then you are in good shape. I always thought that heaver draws were better but then realized by using lighter arrows I was able to mock the heaver ratio of more weight. You so lose some kenitic energy down range but if you have a shot within 20 yards it really won't matter. Most clean kills are within this range anyhow.