After 21 million bitcoins After 21 million bitcoins miners will be paid certain transaction fees but I need your guidance for clarifying following confusions:-


Currently solving a block gives you 25 bitcoins but what is the
reward level after 21 millions bitcoins? 
I understand we still need sufficient amount of verifying computing
power to secure the network even after 21 million bitcoins but do you think people would invest in
powerful machine just to process transaction where the reward level
is lower then the power consumption?
What if  bitcoin community decided to mine for other alternatives
such as litecoin, dogecoin for greater rewards, don't you think it'll
effect the value of bitcoins?  
Do we still have power competition to process transaction?


Thank you
If this happens, you are likely talking of the years following 2140.  If bitcoin survives, it is very possible that bitcoin will be worth millions of dollars.  If so, then perhaps single little satoshis will be worth cents or perhaps what we perceive of as dollars.  Especially if bitcoin is used to supercede as the most common method to use currency.  However america would have to lose a lot of value and do something mighty stupid to lose its number one slot as "the preferred method to hold and spend purchasing power"