Hi extremely lovely to hear from you! I'd be very interested in Poo Goes To Poland, thanks for the offer! I'll PM my email.
PA if I'm somewhere where I can rinse the soiled wipes out, I do so, then store in a draw-string waterproof bag to throw in the wash when I get home. But if not, I usually shove them inside the dirty (washable) nappy and rinse them through when I get home. If you haven't got a waterproof bag (I got a couple in my packs of Pop-In nappies), then make sure you always have some ziploc bags with you - one for clean, moist wipes, the other for the soiled ones.
Let me know if you need any more tips!!
Bc - DD would only sleep on my chest for the first few weeks, but I did eventually wean her onto her Cocoonababy. My feeling is, if you're a habitual back-sleeper, she'll most likely be fine there - your own body heat and breathing etc. will regulate hers.
You can have pillows if you co-sleep, just make sure they're well away from the baby. Best way to do it, if your cradling the baby to breast/under an arm is to put the baby in their own sleeping bag (or whatever) on top of your duvet, well below the level of your pillow. If she's on top of you, pillows shouldn't present a danger to her. I actually used my stretchy sling as DD's covers when she was sleeping on me - it meant I didn't worry about her rolling off me (and the fabric was breathable) - I left it fairly lose.
In the hot weather, you'd probably find a mai-tei sling to be most comfy for you and the baby as they use the least amount of fabric. They're also relatively easy for back-carries too, when you get to that stage! Mind you, I found my woven Calin Bleu cool gauze wrap sling to be fine for me and DD during the summer in Madrid - just made sure both of us were lightly dressed (and used strategic positioning of muslins to shield DD's bare legs from the sun - another trick was to fold a rolled-up muslin in the sling fabric behind her head for extra support. Worked a treat! If you check the FB page, I stuck a load of photos of DD in the red cool sling, if you want to see some of the things I did to help carry her comfortably.

SB here's hoping your DS isn't brewing any bugs.....