We are currently experiencing a flood of requests from bots scraping the forums. Unfortunately it has gotten to the point where it is negatively impacting the site. As a result the forums may be slow and you may periodically experiance an error message.
We are aware of the problem and apologize for the inconvenience.
Haunter is probably one of the few (or even the ONLY) middle-stage Pokémon that actually doesn't look worse than its evolved form.
But Gengar certainly isn't bad either. I'd say that appearance-wise they're about equal; and both of them are milestones (Haunter: first middle-stage that doesn't look weak next to its evolved form; Gengar: first fully-evolved Ghost type and ONLY fully-evolved Ghost in R/B/Y)