Short question, really, really long answer!

Yes and No.  Let me explain.

I would control the pools used.  Pools would be setup as needed based on profitability of different coins.  In a nutshell there will be pools setup for the following algorithms:
CryptoNight, X11, JHA, NIST5, JHA. X13, Groestl, etc  Each of these would be assigned a port number.

As an Extreme example lets just say there are 25 people using the service with 2 rigs each for a total of 50 rigs and lets say 200 GPUs.  Now lets also for the sake of argument assume it's a strange day and profit is changing a lot between different coins (don't care if same algo or not).  

We could mine some x11 Millionaire, some x13 Marucoin, some JHA jackpot and some nist5 TAC.  Now if you only have a rig or two you aren't going to be making a ton to begin with and I'm sure you don't want to have to 4 wallets and do trades for 4 different coins in a timely manner to capitalize on the trends..  So my thought is that I'd use/leverage the full power of the 50 rigs to maximize revenue and trade the 4 coins at the appropriate time for the "group".  This could mean cashing in right away or holding off a bit because the coins already mined are rising in value at an exchange.

Basically convert everything to BTC.  Then using the accounting of shares of each coin mined/traded I could calculate your fair share and send you one btc payment once to a few times a day depending on your volume. (super high level explanation).

Where things will get interesting is that I will be able to take into consideration the time for a block to mature to get it to market to sell. If the coin is going up in price it's worth the gamble, and if the coin is profitable but going down in price or doesn't have the needed volume or block confirmation time is long we can pass on it. The backend can take into consideration trading volume and how much of a "buy wall" is present. Things of this nature. Due to programming already in place the backend will learn what the fudge factor is for each coin and will continually look at it and refine the process.

Also I'll integrate with services like NiceHash (and similar) to be able to rent our MH on demand if it's more then we can presently mine for. We always want to earn the most we can per MH of hash so...

To start for the most part it will just use the "pure" calculators I've built to figure out what is the most profitable coin.  But already built in (without the data) is a "fudge" factor for each coin, algo or pool used.  So as an example lets say a particular coin by pure math should produce 100 coins a day.  We all know it will never be 100 coins long term (luck aside) due to things like orphon blocks, stale shares, network latency, DDos attackes, etc.  So for each coin/algo/provider the system will quickly get smart and learn that coin A only does 95% of calculated amount.  Coin B does 90%, coin C 85%, coin D does 96%. As time goes on it will learn to use the "fudge factor" in determining the "real" most profitable coin.

So in a nutshell I will be able to use the massive MH rate we can all produce as a group to analyze and produce code that gets us the most $ for the hash we have combined.

Now where we will differ from tradition pools is that I will not run a typical pool per say. In other words it's not going to be like "solo" mining with the 50 rigs or 200 GPUs.  I'll be doing a "proxy stratum" for each algo.  So if you are mining X11 you'll point to port 6001 (example). This could in turn use a pool or two running the coin we want to mine.  The advantage of this is that if our "calc" determine we should switch off to JPC (jackpot) then all the shares we have already submitted for X11 will still be good and payable soon. Since we are mining at already profitable pools the income stream should be quick and blocks should not take long. Since we are using one or more other pools for that X11 coin and since all their hash rate didn't go "poof" when we switched they will continue to mine and will solve the block.  We will get paid for our shares.  In contrast to many "multi-pools" they switch coins and you "loose" your shares in that coin until they switch back to it if ever!!!

To begin we'll just appear as a normal user to these pools with massive volume per our account. As we grow I'll try and negotiate with different providers for better rates on our behalf.

Now one of the cool things is that due to the "buy wall" we could have some people mining X11 and others mining JPC while yet others are getting some NiceHash X11.  This will all be taken care of by the backend to "normalize" the income.  So it won't matter to you if you are mining a coin directly on X11 or via a "rental/hash" company.  You will/should make the most available.

Getting back to your original question now.  With all the stuff that can/will be happening on the backend it will be easiest to "normalize" everything based on shares to a common demonstrator which in this case is BTC.  Hence your "login username" will just be a btc address.

Make sense?

Carlo

PS some of the backend is just "brain power" or gut instinct on when to sell/trade, hold or sell for most $.  It's foolish to think it can completely be automated. People have tried that for years and years on the stock market.  Because of this and since I can't do this all myself I do plan on "recruiting" a few trusted soles into the "mix" to help run things.