Is it wrong to be considering a second bike whilst learning to ride one's first?

I have a Marin Stinson "comfort" bike that I'm learning to ride on. It is sturdy and sensible, fine on tarmac and ok over bumpy ground, but feels quite heavy at low speeds and is really not very attractive . I'm thinking about getting another bike next year. Something that I love and that I can use when I don't need to carry the shopping or the child and just want to go out and ride once the girl starts preschool after Easter. I prefer cycling on tarmac/paths/canal paths to anything bumpier, it's generally flat here though there is the occasional hill, and I would like something prettier than my Marin. It would just be leisure riding, though I would love to do a charity ride once I'm good enough.

If I want to cycle in a skirt and boots do I need a bike with a chain guard or skirt guard?
If I'm not seriously off-roading do I really need anything other than a "normal" bike?
If a bike doesn't come in sizes, what size does it fit? eg Electra Ticino
Can you get up a hill with a Pashley?


Bikes that I'm considering are:

Pashley Poppy
The Therese one from here
Electra Ticino 8.

Sorry for all the rambling, opinions and advice welcome. I'm in the UK. Thank you for reading.