I actually love BPB, and the Grand National remains my favourite wooden coaster in the country, infact its my favourite full stop, and I have a lot of time for pretty much every ride there.
The problems for me come from how the park has been operated for the last 25 years or thereabouts, and they stem from opening times being ridiculously short, night rides being almost impossible to get, even when they do so called late night events, it's often not dark by the time the close and when it is, the only coaster still in operation till the end is the National, which means its usually got a 45-60minute wait and is only running 2 trains usually.
Add to that the dwindling capacity park-wide, the slow service at catering units, the lack of atmosphere and the blatant ignorance to long problems that have been around for many years, the Grand National lap bars hurting people as well as its trains being too heavy for the track and it's overall poor throughput and reliability, Streak/Avalanche/Steeplechase having a lower capacity than what they should, and far too many rides being lost with no replacement, Black Hole, AstroSwirl, Cableway, Wate Chute, Space Invader, Monorail, Wild Mouse, Trauma Towers.....