If mining LTC and the price jumps in the future when you have quite a few of them, awesome.
If mining multcoins converted to BTC, LTC jumps, your stuck with previously low mined BTC.
What are you miners take on this?
If mining multicoins converted to BTC, and you buy LTC with those BTC, you're creating buy pressure making LTC more likely to move.
Also, it depends on your hardware? Are you talking about Scrypt ASICs or GPUs?
LTC is already one of the most profitable Scrypt coins, so just mine that directly if you only have ASICs if you believe LTC is gonna jump.
If you have GPUs, please, mine something else. The competition of Scrypt ASICs for GPUs is way too high, and you can get more by multipooling X11, Quark, Nist5, whatever other algo than Scrypt (& sha256 :p ) and buy LTC with the profits you get from that.
But just like atsuky said, it's all a (calculated) gamble