How should I treat a new cipher release like Spritz?
Nobody can tell you not to "have fun with it" but I would strongly recommend you to first study attacks on other ciphers. Spritz (Rivest &amp; Schuldt) fortunately mentions a lot of research on its predecessor, RC4. This makes it a rather good starting point in my opinion.

It is necessary to understand the linguistics and mathematical constructs that are used. Jumping into crypto-analysis without a good understanding of the concepts will not get you any reasonable results. 

If your main competence is to create a fast/secure implementation of cipher algorithms, then go for it. In the worst scenario an attack is found or the algorithm never receives wide popularity.

I don't see the big difference between 1) and 3) outside your own state of mind. Again, nobody can tell you not to be exited :)