You're right, Iain Stirling is way better than Marcus
But yeah (and I know this has been said hundreds of times), Love Island is actually more like Big Brother than Big Brother itself is. I guarantee over half of the detractors would like it if they gave it a shot, I wasn't expecting to stick with it when I first gave the revival a go but it's very well produced. The editing is fairer, the twists are better executed, the casts are more 'normal' than BB's and the showmance aspect - despite being the focal point of the show - plays less of a prominent role than you might imagine
In the last three years, I'd say only BB17 was marginally better than it's Love Island counterpart