the 3* is the worst value on the wheel. That's kinda the thing though.
4 spins with the 3* totals 12 stars. It only costs 11 stars for a Lvl 4 Nin or Attack Magatama.

Less than 80 coupons for a level 4 magatama that costs 135 in shop.

Yes, it's weighted heavily towards giving you the 3* - but even if not getting any of the "good stuff" on the wheel then you're already getting perfectly good value!

Now, you'll occasionally get the sealed scroll and somewhat regularly get a summon scroll... and, of course, there are spots with more than 3* and the 50 ninja frags. All of those spots are gravy. They're bonus.

The Lucky Stars Wheel is amazing for anyone that has ninjas that care heavily for either NIN or ATTACK.