All landscape maintainers have their preferences, but the most important consideration is the use case. One size doesn't fit all.
I'm a huge fan of mulch. Mulch packs a good punch, and can be source free of cost:
Low maintenance—3" of mulch is efficient, effective, and user friendly when it comes to maintenance. Weeds detract from beauty and steal water from plants, so I prefer to invest the time into nabbing weeds when they are little and easy to pluck. And they are easy to access with mulch: simply quickly sweep aside the mulch to access the soil, then sweep it back with the your instep like tapping a soccer ball. There's less bending. The material is lightweight. Additionally, mulch tollerates dust from wind without discoloring or mudding your aggregate.
Cool temperatures—Low heat absorbtion in summer means that you'll feel cooler hanging out in/around your landscape. Mulch dissipates heat quickly and acts as an insulator for the soil underneath.
Retains moisture—Mulch holds in moisture, lowering water usage.
High beauty—If one gets passed me, I go for the juguler (taproot).
If you're gonna use mulch, consider some plants prefer sandy soils (not mulch). I've found that mixing the first 12" of soil with a 50:50 ratio of soil to sand or Indian Trail Mix improves percolation.
Keeping the mulch away from the root ball is also helpful in preventing fungal buildup around the plant's rootball. Regularly walking in the mulch improves airflow. The biggest contributor to failure (root rot) is owners who sprinkler-water or water too much. Mulch traps moisture, and that's why I like it over aggregate.
Just because mulch packs a good punch doesn't mean that decomposed granite (DG) doesn't! Indian Trail Mix is a form of Decomposed Granite with smaller particles less than 1/4"-3/8"and stone dust, producing a flat, smooth surface. My decomposed granite preference for pathways is Indian Trail mix (no gravel) because:
Leaves are easy to remove via a push broom or leaf blower.
Easier to patch DG when ants take up residence without having to clean gravel to remove dirt.
However, if you are going to use Indian Trail Mix for plants, consider planting A LOT of plants so as to cover the entire area so that the DG has less direct sunlight (plants will feel just as cool in summer as mulch if covered). If you enjoy seeing the contours of your plants and don't want high plant density, consider mulch.
Again, just because mulch packs a good punch doesn't mean that decomposed granite (DG) doesn't! Decomposed Granite (vs. Indian Trail Mix) is 1/4" minus to 3/8" minus, meaning 1/4"-3/8" gravel mixed with all the smaller particles and stone dust. The result is that the 1/4"-3/8" floats to the top, producing a uniform sized small stones look-and-feel, leaving "Indian Trail Mix" to fall to the bottom layer.
If you like the look of thatch and thicket on your gravel, consider that doing so supresses weeds.
If you like a clean look, leaf blowing might require extra effort: you'll want to use the lowest setting and hold the blower's nose high at a shallow, horizontal angle to skim the surface.
If you have high-density garden, a leaf blower might not be possible. Instead, you can dispose material as you deadhead.
If you have honeylocust trees in your neighborhood a low blower setting will move them at low speeds, but larger leaves such as catalpa or ash might require removing leaves by hand.
I keep rock to a minimum because it's not easy to maintain over time without regular herbicides. But, how you use large river rock really depends on the use case. Large river rock is exceptional at handling moving water, so it's a great solution in and around downspouts for erosion prevention. But, it can be hazardous for walking paths.