It's not desperately useful (as it limits you to only Y B or H buckets) but if you log in as a BAEC member, you can select an additional option on the "Ticket Type" drop down list on the home page (and elsewhere) called "Lowest (Earning Full Tier Points)".

It would in reality be much more useful to most people to have a "Lowest (Earning Half Tier Points)" option though, which restricts you to the K, L, M, N, S and V economy buckets - but then I think 4 different "Ticket Types" might be a bit confusing to the average person!