The west coast of the island is out and back travel (with a very few exceptions) so considering time available, you probably need to prioritize your chosen coast spots. There is a new paved loop from Victoria-Port Renfrew-Lake Cowichan. Used to be dirt and very rough in spots. Lots of forest/logging roads to get lost in in-between.
The road from Port Alberni to Bamfield is over 50 miles one way and mostly hard packed maintained dirt/gravel with lots of big log truck traffic. I towed a boat to Bamfield one year and took 3 hours. Only 1.5 hours headed back out with the trailer empty (drove it back via water) and the roads freshly graded. In Port Alberni, Ucluelet, and/or Bamfield you could catch a day trip on one of the supply/taxi boats (MV Lady Rose and MV Francis as I recall).
The Barkely Sound Islands are worth the time to see by boat or kayak. I did a 4 day guided camping kayak trip in the Broken Group Islands last August, somewhat spur of the moment, for something a little different. I have fished those islands for many years before, always wanted to kayak them they are so kewl
. They have lots of 1 day trips also. I think it would really spice up your visit to the island and give you lots to talk about on the way home. Tofino and Zeballos have these also as well as most of the populated east island coast areas. Many campgrounds around.
If you head out to the coastline From Port Hardy to Winter Harbor, plan on 2 hours each way. Slow dirt roads. About 1.5 hours each way from the highway to Zeballos. I liked the Zeballos drive though not much there when you get there.
Some things for you to think about. So much to see out there.