If it helps ease your mind - I will share my story below

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For the last 2 years I have run 2 iPhones (one personal and one work). Always had a 'normal' size for my personal which is my main device and I update every year...... and a 6 Plus for work (2 years) which usually stays in my bag. Using only occasionally and never keeping in my pocket, i always thought of the plus as very big and not so friendly.
However, knowing that the 7Plus was likely to feature some extras like the camera, and really wanting a battery life improvement, I decided that for the last 3 weeks I would switch my phones and use the plus as my main device - thereby 'testing it out' before ordering the 7.
The results...... i love it (and have ordered 7Plus). After 3 or 4 days I genuinely didn't notice the size and in fact when using my 6S it feels ridiculously small. The Plus just feel normal. And pocketing it really isn't an issue as it is no thicker than the normal size (and I wear reasonably skinny jeans!). I'd actually go as far to say that I am now so used to it that sometimes I look at it and question if it is the normal or plus! size has become completely irrelevant!