Yes, I think you are missing out as there are some very good gins to be had and I'm sure some pretty naff ones as well. It's like so many "craft" drinks, too many makers jump on the bandwagon.
With whisky and gin you're comparing chalk and cheese. Try viewing them separately. You'll know as well as I the variety of good whiskies is huge not so with gin. Personally I'd never drink whisky with anything other than water, bit of splash if it's everyday stuff and a tiny drop or nothing in a malt.
I can't drink gin by whacking it together with ice and tonic. Proportions are very important or the flavour gets masked. For me to make a good G&T it's firstly important to chose quality gin and tonic plus lime or lemon juice and ice. This is our bog standard Friday night G&T. Glass full of ice, 60ml Tanquery No.10, 150ml Schweppes or Fever Tree tonic, squeeze of half a fresh lime.
Once one starts drinking flavoured gins getting the balance right is more important to avoid losing the flavour. If you wanted to try one I recommend Ophir Spices of the Orient but change the proportions to 70ml and 140ml. You can get this in supermarkets for £16-25 a bottle.
Our local Cuckoo gin is fantastic but you're looking at £38-40. I once got a bottle of French gin for my birthday made by an Armagnac producer, all it needed was one ice cube and sipped neat. Nectar. £50 though!
@Tenkaykev is right about many. I make cracking gooseberry gin at home from my own fruit, sugar and £14 litre of Tesco gin.