I might agree that Felix has not developed up to his full potential yet, but I think he has what it takes.. His books, like his Father's, do exactly what I buy them for, they transport me from my Inland Southern California home to the heather and downs of horse-country England.. Dick did an amazing job of character and place description, maybe taking a clue from female writers, spending copious amounts of time describing meals, clothes and rooms.. For a foreigner like me, I found that essential to "transporting" to the scene and feeling "right there" with the action. Gerard Logan, in "Shattered" has always been my favorite Francis character. His love of simple food like fried (or were they poached?)eggs, has stayed with me for years, and has permanently affected what I like to eat on a (rare) rainy day.
I see all these elements in Felix's books. Not as good yet, but from someone who has tried to "write a book" with about 4-5 false starts, I have great respect for anyone who can see it through to the end.. Like dancing, it takes a while to get into the swing of things.. but from my perspective, If you liked Dick Francis, and you can cut the boy some slack for being a different person, I see no reason why you wouldn't continue to enjoy this franchise.