I don't think it's particularly practical to speculate about what Weezing could have been. :0 Let's stay on topic here and focus on what Weezing actually DOES have to work with.
So to me, it looks like we have a few distinct standard-ish sets emerging here... The semi-offensive Hazer, sans Stockpile, and the more defensive Stockpile variant.
Semi-offensive / Utility Weezing
- Fire Blast
- Thunderbolt
- Will-O-Wisp / Haze
- Pain Split
Weezing Whall
- Stockpile
- Pain Split
- Toxic / Will-O-Wisp
- Fire Blast / Clear Smog
You could, theoretically, mix these together, but I think Weezing with offensive moves and Stockpile both tends to suffer from 4-moveslot syndrome. Thus, you can have the offensive wall/hazer which forgoes Stockpile in favor of being able to hit things supereffectively (most notably all Inconsistent users save Smeargle), or you have the dedicated wall that utilizes Stockpile for defense and Toxic / Pain Split (or Will-O-wisp, if you like) to wear things down. Clear Smog is also a good hazing option on the latter set, but doesn't work against Inconsistent Substitutes, but that's not to say it doesn't have other uses.
These are two sets I'd like to see in the OP.
Thoughts?
Edit: Ah, I forgot EVs in the sets. I can add them if deemed necessary.
...
...please don't make me add them. Dx I'm terrible with defensive EVs. =_='