I was just forwarded ten rules for best research.
The contrarian in me wants to find all the flaws of it, such as the fact that only a limited number of people can end up famous, but there's definitely something to it.
The temptation for me is to find the low-hanging fruit, rather than the important problems. More analogously, I have a fancy hammer and a screwdriver, and I want to go around banging all the nails sticking out of the walls and tightening all the screws. The nails and screws that I have found are important ones, and even ones that get some recognition, but I do not know that they are the most important issues.
It certainly does take courage to come up with the list of unsolved important problems, and tackle them, but you also have to be sensible about which problems are solvable. A physicist who decides that time travel is the most important unsolved problem may end up making an important contribution, but it's more likely that they could just waste their time. In that sense, the physicist would be better off finding low-hanging fruit.
Right now I am consumed with just finishing the projects that are hanging over me, and I have a hard time seeing the future. If I were so systematic as to conceive of myself as having a research portfolio, though, I could treat it as an investment portfolio, which it is. Some projects could be high risk high reward, and others could be good bets, but medium reward.