I don't really buy that many blacks and actually blacks are the one tea I'm happy to drink out of a bag if offered! Though I still find most bagged blacks are pretty horrid, I must say. That's not to say I don't buy black tea or that I don't drink it often, which would be very much untrue. In fact, within the last 12 hours I've consumed 64 oz of black tea, which is about 1/3 of the tea I've had in the last 24 hours. It is just that I'm rather content buying cheap Rwandan or Assam tea or something like that and brewing it up strong in large quantities. Really, there are too many delicious greens and oolong out there for me to really focus on blacks. In fact, I just ordered 20 new teas and only one was a black... and this was some lapsang from Adagio. I'm waiting for my fiancee to return from visiting family before ripping it open, so no lapsang for me for another two weeks! Checking my tea wish list also brings me zero blacks... but I feel that in the future I will look into opening myself up to exploring this end of the spectrum.
On the topic of bitterness, sometimes I purposely try to bring it out of my teas as it is a taste that I enjoy being walloped over the head with from time to time. The thought of watering down sencha.
To each his own though, of course. Whatever way one can appreciate sencha is a good way, in my opinion. Dilution beats sugar and other additives any day.