In post cold front conditions and/or really hot, bluebird sky days, I’ve experienced success in downsizing my presentations. It’s also popular musky tradition to use smaller lures for early season results. The pros don’t necessarily endorse this as a primary early season requirement for success but it is popular in belief and practice.
Sure, you can use a smaller, lighter setup for this or simply adjust your reel settings, but a spinning set up will chuck those lures a little further for more water coverage. You can use a spinning rod just as accurately as a baitcaster if you put in your time with it. Also, if you’re ept to using both set ups, for me (which I’m more the exception than the rule) it means switching arms for throwing the lures. This helps me with fatigue issues, which is a nice perk to this sport.
The advantage is water coverage with lighter lures and the ease of casting them in all conditions with a lower risk of backlash. Disadvantage is that spinning reels don’t have the durability of heavy strain like the casters do. It doesn’t mean it can’t be done though. It just means you have to accept a reality of this setup. Also, the factory rods I’ve seen are indeed to wimpy in the power department. Heavy lures really aren’t an option. It’s lighter and/or smaller or nothing. This is why I’m having a custom done.
For now, I’d really stick with the casting outfit you’ve put together. It’s important to learn the techniques and skills with this stuff because overall, it is the better suited for your objective. But, for an option, I can let you know what I find with this custom over the coming season by reporting it here. It may be a challenge finding the right reel for size, strength, and weight balance as well.