I don't get that whole this day I am carrying one gun and the next day I am carrying another gun thing using a media-based perceived threat level. Not only is it impossible to predict the situation where you need the gun, but different guns means inconsistency (different form factor, holster, carry method, capacity, caliber and/or manual of arms). I train and practice with what I carry and I carry what I train and practice with. If I am in need of more "firepower" than I carry, then I am in need of a rifle or shotgun. The two exceptions I can think of is when a more powerful caliber is needed to dispatch four-legged threats (e.g., when hiking) and when the usual carry method does not work (e.g., when jogging or skiing).
For the record, I usually carry a Glock 19 with XS Big Dot sights loaded with 15+1 rounds in an IWB NSR Tactical holster and two 17-round spare magazines in a Blackhawk magazine holster. That's 50 rounds of 9mm.
While hiking in the woods, I carry a Glock 20 with XS Big Dot sights loaded with 15+1 rounds in an IWB NSR Tactical holster at the same position and two 15-round spare magazines in a Blackhawk magazine holster at the same position. That's 46 rounds of 10mm. In both cases, Glock 19 and Glock 20, it is a not too different form factor, a similar holster, the same carry method, the same capacity, and the same manual of arms.
When jogging, I carry a Glock 26 with XS Big Dot sights loaded with 12+1 rounds in a SmartCarry crotch holster and one 17-round spare magazine in the same holster. In this case, it is a not too different form factor, a completely different holster, a completely different carry method, close to the same capacity, and the same manual of arms.
When skiing, I carry the Glock 26 with XS Big Dot sights loaded with 12+1 rounds in a DeSantis Nemesis pocket holster and one 17-round spare magazine in a DeSantis Nemesis magazine pocket holster. In this case, it is a not too different form factor, another completely different holster, another completely different carry method, close to the same capacity, and the same manual of arms.
Even in these 4 different cases, it requires me to train and practice 3 different draw and reload techniques. However, the rest is the same due to a not too different form factor, close to the same capacity, the same manual of arms, the same trigger and the same sights.