- because you skipped scrypt and scrypt-N which might be the most profitable in a particular time interval and auto-switch X11:4336, X13:4337, Keccak:4338 ports will be closed, you'll be still mining X11 on nicehash X11 backup pool: X11:3336 (Note: with this configuration it might happen that X13 might still be more profitable then X11, but you'll be mining on X11 backup pool because it might happen that profitability will be like this: Scrypt > X13 > X11 ... and since Scrypt is the most profitable, X13 and X11 auto-switch would be closed).
I think you can add another group of ports for only cold and energy efficient multialgo mining - like X11:5336, X13:5337, Keccak:5338 (may be also groestl) - I think this group of ports will be popular

i agree with you , currently i manually switch between those algos but if we could have ports specific to those it would be that much easier to manage.