Until adding a pellet smoker to my arsenal a few months ago, charcoal and wood chunks has been my smoking method during my hobby over the past 4 years. When I began with the pellet smoker, not only was the taste much different, but I also lacked a rich bark that I've become accustom to from charcoal
I've made some tweaks and here are a couple that I feel have contributed to a better pellet experience (I reserve the right to change my mind on this):
1. I start at 225*f or a tad higher. When I first started using pellets I'd start a smoke at 180'ish because that's the feedback provided in the manual for more smoke. Some very brief reading of two or three folks whom I'd consider experts suggest that good bark formation requires temps north of 200f, so that's what led to my journey of 225* (and I always smoke at 225-285'ish on my charcoal units, anyway).
2. I now mostly use Lumber Jack's Char-Hickory pellets because they contain 10% charcoal (still what I'd consider a low content but some is better than none)
I still don't get the taste I've been used to from charcoal but I'm at the point of thinking that just because I'm used to it doesn't mean it's the optimal flavor. Honestly, I do get some smoke flavor from pellets and if I have leftovers in a bag in the fridge I can smell it when I open it.
In another thread you mention a friend who uses a Smoke Daddy. I've heard of their deflector that allows wood chunks to be added but I'm not aware of an add-on of theirs that requires any hard modification. I know there's another vendor who offers a downdraft add-on, though. Here's my thought: if you know of an add-on that delivers what you want then--unless you're contemplating returning the smoker--they will not know that you drilled holes if you need service components due to a failure down the road.
I tried a smoke tube twice but it did not seem to make a difference to me. In Rec Tec's owner's manual (or maybe it was on their YouTube channel) they suggest that wood chunks or chips can be added directly on the deflector shield, so perhaps that's something to consider, too.
Good luck in your endeavor.