Thanks to both for your thoughts.
The photo of the leftovers doesn't do the plated dish justice as it was just chucked into the container when the rice and sauce were cold. The plated dish looked the business, but the food was just so bland I could hardly believe it.
Of course, I'm making no comment on Dipuraja's original recipe as I used variations on the different components, but I'm happy with my other BIR cooking, so this biryani was something of a disappointment. OK, it was my first ever, but still...
Maybe it's just nostalgia on my part as I haven't actually bought a TA biryani for many years, but my memories (such as they are!) are definitely positive.
Maybe I expected too much from the dish. I started off this thread saying,
"I've never found a recipe that "looks" right" and, having thought about it, maybe I should have substituted
right with
complicated enough. On reflection, many of the recipes on the web seem a bit cheffy, but when you look at recipes such as
Abdul Mohed's Chicken/Lamb Biryani, the ingredients list is pretty short and the cooking method is simplicity itself.
I also referred to 3 packets of Laziza Biryani, Bombay Biryani and Sindhi Biryani spice mixes I bought on offer a while ago. Although I haven't actually used them yet, the recipes on the back reflect Abdul's recipe in their simplicity of ingredients and cooking method. And not a sultana in sight!

I now wonder if the apparent lack of biryani recipes on the forum reflect a general disinterest in the dish or whether, in fact, no-one seems to have a decent recipe.
Whatever the answer is, and in the absence of a firm recommendation for a "proven" biryani recipe (whatever that may be!), I think I'm going to try Abdul's version as well as the recipe suggestions from the commercial spice mixes and see how these "simpler" versions compare against my fading memories of a BIR biryani.