I keep reading everywhere that skinny jeans are back in fashion.
The people saying they're unfashionable clearly don't keep up with trends!
Leggings can look terrible if the quality is bad, or you're the wrong shape because they don't hide anything. Some people look god awful in leggings. Just because it's "fashionable", doesn't mean you should wear it!
You don't say how old you are, so it's difficult to pick out actual items.
I think skinnies are a good choice and more versatile than leggings. Pair with a tshirt/vest top and chunky knit cardi, oversized tshirts look good and praticially any jumper.
With leggings, you need everything to be long enough to cover your bum and crotch, unless you've got a great figure and are young.
In summer, I would ditch the cropped trousers and tunic look. Its very dated, mumsy and unflattering.
You could try loose linen trousers (can go for cropped, but they make you appear shorter and larger than you are) or palazzo pants and vest top or tshirt.
Midi skirts and dresses are flattering on almost anybody if you get the right style. Plus they're short enough to throw on some wellies if you need to.
A-line denim shorts are a great choice as they accentuate your waist and bum but are just long enough to cover most of your thighs. Again, pair with a tshirt, vest top or shirt.
Linen shirts or tops are good in warm weather.
I like my straight (but loose) ripped jeans in the summer too, if it's not blazing hot. Mom jeans are also considered a fashion staple.