I've been experimenting with pate for years, with various success, but here is my basic pork pate.
Sautéed onions/shallots
1 lb liver, I lb very fatty belly pork, and a wee bit of bacon if it is in the fridge.
That is basically it, everything else is seasoning. Pate is not a scary thing to cook, it is really just poncey meatloaf. Get your basic proportions right, get your head around technique and then the flavours are anything you want them to be.
At the moment I am perfecting a scottish theme pate, with the above meat mix ground together with heavy on ground juniper berry and whiskey, light on thyme, nutmeg, allspice, plus salt and pepper.
I don't line with bacon, I used to, but Raymond Blanc convinced me not to.
Jane Grigson's classic on French charcuterie has some
excellent starting points in regards to flavours.
As good as her recipes are though, she is a little light on technique and is vague with cooking times. An overcooked pate is grainy, a bit crap, and after originally oohing and ahhing at your pate, guests will not come back for seconds.
My (pate making) life changed when I had a look at Raymond Blancs recipe from Kitchen Secrets, here is the BBC link, the book goes into a bit more details
He cooks pates very very slowly, and measures their progress scrupulously with a meat thermometer. I haven't made Raymond's recipe, but I copied his technique exactly, adding a few more centigrade to the final temperature because I was cooking with pork liver, and not chicken liver.