I'd like to get no stronger than 4.5% ABV.
And any simple ale would due for this crowd.
As someone who's drunk in British pubs all his life, I think there's a real sweet spot for bitter around 4.2% - below 4% I feel you start need to messing around with "extras" to help with body but for classic best bitters all you need is quality "proper" ingredients.
British beers are all about balancing all the components. Start with the yeast - you need a characterful yeast which probably means one that doesn't attenuate too much. I'm still working my way through the main liquid homebrew yeasts but WLP041 is definitely one I want to go back to even if I suspect I'll end up adopting a Brewlab strain as my house yeast. I know WLP006, WLP023, WLP025, WLP028, 1318, Imperial A09 Pub and the WLP022/1469 pair all have their fans.
Grist for a best is pretty easy - ideally a premium British malt like Otter or Golden Promise, ordinary UK pale will do, or at a pinch US 2-row with some biscuit or Victory to help it out. Generally if you're going to put crystal in a British beer you want at least as much sugar (preferably invert/golden syrup etc) to balance it out, but you can probably get away without the sugar if you're only doing <=3% crystal. That quality pale malt is providing most of the flavour.
Hops - can be anything really, especially given your comments on your "crowd"
Can never go wrong with Goldings, although mixing in some Bramling Cross is even better, but the likes of straight Challenger or First Gold will work, but these days even in the UK you see quite a bit of Cascade etc in there.
Be generous with the gypsum - >150ppm calcium and sulphate, but don't overcarbonate. Low abv beers tend to struggle a bit in keg IMO, they benefit from the lower carbonation (1.2-1.5vol) of cask conditioning (or just very gentle force carbing), although you need a bit more than that (say 1.8-2 vol) for them to feel right in bottle IMO.
Or for something 3.2% and hoppy using all the tricks like oats and melanoidin see
this thread.
Glucoamylase will thin out your beer and increase the alcohol you get from a given grist, which may not be what you want....