I've gone out of my way to fly as many different types as possible since gaining my licence. Some are undoubtedly more daunting than others, but finding the inner resources and developing the knowledge and skills to operate them safely is a big part of the appeal of flying for me. As time goes by, what once appeared daunting becomes less so - it's how you know you're learning.
The first time I sat in the Yak 52's front cockpit I felt distinctly daunted. After 30 hrs on type, I find it straightforward and friendly, though like FFF in his Europa, I still find I have a raised pulse and dry mouth sometimes in the moments before I start the engine and begin to taxi. I don't mind that - I think a certain amount of it helps me focus on the absolute seriousness with which I have to treat the whole endeavour of flying, even if it is for fun. The Pitts S2 I still find rather daunting, and in less guarded moments have been known to use the word 'intimidating', but I know that in time, and given the cash (!) I will come to terms with it.
One aeroplane I expected to find daunting but didn't is the Stearman - for some reason, perhaps its sheer size, I expected it to be incredibly heavy and physically demanding. But in the air I found it precise, talkative and remarkably co-operative. However I only have one flight under my belt and I am certain, as with all the aeroplanes I fly, even the PA-28, that it is capable of showing me a more challenging side. Even a pussycat will bite in the right (wrong) circs, like when you reach the end of a lovely grass runway in a Tiger Moth and find you can't turn off along the taxiway because of the slight crosswind.
I appreciate that people learn to fly for all kinds of different reasons and many, including a good friend with whom I've often discussed this, have no ambition to fly anything other than a nice PA-28 or C-172. Good luck to them - for those who prefer to challenge yourself by flying long complicated routes, developing your instrument flying, traversing busy complex airspace, these are all worthwhile and rewarding things to work on, and quite capable of being every bit as daunting.