Honchkrow doesn't have WAY too many weaknesses... in fact, to my knowledge, it only has 3: rock, ice, and electric. Dark/Flying is actually a nice typing, because Flying cuts out Dark's Bug and Fighting weaknesses. Did you give your poor Honchkrow a decent nature and EVs? a speed boosting nature with some good EVs can make Honchkrow a beastly sweeper, or you could just make it a Choice Scarfer. Honchkrow's attack stats are nothing to laugh at. Dark and Flying have a lot of synergy and can cover eachother very well, Honchkrow can easily function in standard as long as you can predict Stealth Rock, Stone Edge, and Ice Beam. Electric attacks may have given you a rough time on the E4, but they are not nearly as valuable in the competitive environment.
And Spiritomb? pathetic? Hardly. I'm sick of everyone assuming it sucks. Has ANYONE actually LOOKED at its stats? they all throw down except for its speed and HP, which in exchange for having no weaknesses I think is a pretty good tradeoff. WoW and Confuse Ray are always a good pair, it has Nasty Plot, Calm Mind, Hypnosis/DreamEater, and has two good stab attacks, both of them Special, plus the ability to learn Psychic and Silver Wind for a little extra type coverage. It may not strike super effective hits on a lot of things but it also hits many many things for neutral damage which can be valuable.
It is slow, but with good tanking and attacking abilities, you don't need speed. Speed is needed for pokemon that have the attack power to OHKO, but not the defenses to survive a follow-up attack if they don't... Which Spiritomb does have. Attack power is a constant, you aren't going to sweep a skilled trainers team without pokemon that have decent attack stats. Defense and Speed however, those are where the compromise happens. Good Defenses=don't need Speed... and vice versa.