Hi - I'm new to cryptocurrency trading and need advice whether to trade on ETH/ALT(Crypto) or BTC/ALT(Crypto) currency pairs.

I understand the whole market is tied to Satoshi/BTC ratio and not fiat currency (expt Tether) and this is where I was making BIG mistakes when trading i.e sometimes keeping the BTC or ETH was far more valuable than converting to an Alt coin in the first place.

ETH seems more stable, my concern being that when I sell the crypto into either BTC or ETH then the value of the BTC/ETH changes and if I dont quickly buy something else then any profit diminishes. What do most people use ?

What is the ideal "store" for profit in these markets since you cannot convert to fiat currency without the hurdles of transfer costs ?