Kyle, for annuals/seasonal plants like vegetables, what you are using is fine. By the time your potting soil starts to decompose and rot and cause harm to your plants, you have harvested your vegetables.
Mixing with perlite is a great idea to improve drainage and help with compaction. Home Depot sells a 2 CU bag for $16.97. If you have a cheaper source, please let me know. Throw some rocks/stones/pebbles at the bottom of your container. Your plant roots will extract minerals from them. Personally, I would use compost as a mulch and then use your pinewood chips as a top mulch to help retain moisture and in our So Cal heat, our container plants need all the help they can get to conserve moisture. Wood chips tend to steal nitrogen from your plants because that is what it needs to decompose and unlike living plants, it cannot take nitrogen from the air. I would supplement your compost with a high nitrogen source like alfalfa meal or fish meal to make sure there is plenty of nitrogen for everyone. Also, I agree that Kellogg Raised Bed and Potting mix is better than the G&B mix for your vegetable plants because the G&B mix has rice hulls and rice hulls do have arsenic. I don't know how much vegetables will take in arsenic, but I am conservative. If you have some already, use it for your flowers and non-edible plants.
Now if you were growing plants that are not annuals, then you would need a different potting mix. As I mentioned before, I grow plumerias and crown of thorns all in containers. I have 18 varieties of plumerias in 20 containers and 19 varieties of Crown of thorns. I would never put them in any potting mix that has recycled forest products as the first ingredient. That just continues to decompose and rot the roots. Root rot is not from overwatering, it's from rotting/decomposing pottings soil. I've learned that the hard way. That's why I mix my own potting mix. Compost and other organic matter belongs on top, just like what happens in nature. Leaves decompose on top of the forest floor. Peat moss decomposes very slowly, that's why I use it.
This year I am growing some vegetables and lots of tomatoes. I was slow to start on the tomato seeds and not ready to transplant to large containers (except for the ones I bought at the local nursery). I still want to experiment with the coir/pumice/perlite mix and will do that with my vegetable plants. I may even try some plants in just pumice and pebbles, (but lots of mulch on top, of course.) Will update at the end of summer!
FYI, you can get pumice from local topsoil companies that sell by the truckloads to landscapers. Just call and ask if they sell bagged products. I get about 35 lb bags of pumice for $7 each that way.
Hope that helps! Happy planting!
Yvonne
