Perhaps unfairly - and more a frustration/vent as it's all the ingredients of a good network - buses around Cardiff
A hourly 8 bus (City - Grangetown -Bay) through the day for the population it serves is so far from the potential the route has to offer
Any of the evening services on the basis the frequencies are so poor (we recently caught an 11 that was circulating Splott 50 minutes late on an hourly service...which led to almost everyone being unhappy)
First Bus 304 on the fact it begins as a semi-decent express before a grand tour of South Cardiff and the Bay
30/X30, Newport/Cardiff Bus would easily justify a more regular service along the corridor and increase patronage, especially during gaps in the train