Anything 4 
or less? No. There are quite a few mid-range hitmen that resides on the higher-end of that spectrum. The number of tides it can turn if it decides to turn something like that up early can be over 9000.
Think about the initial cost of the beacon though. If it generates a powerful creature early with that cost, it wouldn't be any different from just summoning the creature from your hand quickly. The creature would already come up early even without the beacon that isn't even guaranteed to generate that exact creature or even generating a creature at all.
