[inquisitor]

I think it's quite hard to keep track of SIM cards and changing tariffs for so many countries. There are so many national specifics, a lot of prepaid SIMs cannot be recharged from abroad and so on. Regarding public transport tickets these are personalized in many places and sometimes you even need to personalize them upon purchase.
This could only work smoothly if you had agents in each country or agents covering few countries, which would supply customers with SIM cards, transport tickets etc. (maybe add power adaptors to your list).
The question however is how this could become economically viable. You would have quite a lot of work with each customer and you would need to charge quite a premium over your own costs to earn something with this. However you are aiming at people who want to save money on their trips and with such a premium you would reduce the acutal savings.
The idea is nice anyway, but I wonder how to create a viable business case from it.