All-in-one Service for Cryptocurrency I'm a noob in cryptocurrency and may ask really a stupid question.

Why no site covering everything(Wallet+Exchange+In-house Pool+Mining Cloud Marketplace+ICO) at once, so I can just join and get wallet and start investing my money either,


To buy cryptocurrency or
To buy miner to mine on in-house pool (option to use outside) or
To ICO


in a single site even an app by touching some actions?

Regarding wallet+mining cloud, I know Nicehash, which seems the closest but still I need to set up a pool and understand how their reverse bidding works.

I'm looking for a site where a user doesn't need to know about detail of crypto algorithm or concept of pool or anything but UI for invest X amount then you can earn Y per day/month by selecting currency and mining cloud sorted by ROI.
The answer to this is probably much larger and more general than just being applied to your question.  From a generalised point of view, businesses that specialise in certain activities are able to master them, which in an even more general sense, is the same reason usain bolt never competed in javelin and high jump.

More specifically, exchanges and wallets ARE combined.  All user accounts in exchanges have wallets in order for their users to be able to hold their coins there.  Admittedly the wallet systems in exchanges are different, in that they are only representations of the value you’ve transferred to the exchange, and not actually a wallet in which you have key-control over, but still the same purpose is served.

With regards to combining mining and trading, there is very little benefit from combining these two, in that there are no reductions in complexity or increased efficiencies for users to be had here.  Transferring coins from a mining pool to an exchange, or visa versa, is easy anyway, and if you were trying to establish either of these businesses focusing on one of these would reduce the amount of resource-splitting needed to successfully set up the conjoined version.

ICOs are not really location dependant and can be run from platforms like waves, or from the website of the ico.  ICOs and mining are quite incongruent, in that there is very little benefit from crossover.  A platform to handle trading and ico offering in the same place is however more of an interesting concept.