in my opinion there is no wrong or right here, this is pretty much a very personal matter, it has to do with your workflow, history, financial attitude, style, dreams and so on. it is pretty much like people's sexual orientation/taste/fetishes... everyone is different and enjoys different things... personally throughout the years i found myself holding on to 3 developers only, they are answers to all my dev needs, which are HC110, 510pyro and rodinal (Paranol S in my case), now that i am reflecting on this, it sounds like shelf life and convenient are very much top of mind to choose these, coz i am not like a university lab or a commercial lab that has a regular schedule of in and outs... my photography life is really organic, I take a lot of shots when the season, reason and light and my mood are all aligned and then maybe in 3/4 months time i want to process the big pile my un processed films, then i see my xtol or d76 stock solution have gone bad or need to mix a lot of powder etc anew again, so this is how these three became my first choice .... although I have to confess that sometimes i miss my good old powder mixing for things like microphen for example so I will break my own rules/styles/habits ....