A timeline of events that show the early Scottish culture did not meld/erode Pictish culture but events could mean the Scottish failed or that the Picts survived and there was a relatively modern Pictish country.
I haven't gotten around to reading it but the book Caledonia to Pictland: Scotland to 795 would probably provide the best background reading for the period on this topicThe problem with doing this is that the process is so poorly attested that while we know it happened, we can't be sure of why and how that happened.