There really isnt any right or wrong way to build your wealth.. Aslong as it keeps going up your doing good.. I made plenty of mistakes, where I would have made much more if I could fortell the future.. At one point I had so much ETH, and I sold most of it at $18 and though i won the lotery.. well all that ETH would be worth over half a million today.. I also sold a whole bunch of BTC at $1,600 and watched it climb to $2,400 without me.. luckily there was a dip in may so i got it all back before it went higher .. but those are examples of my not being able to hold because I am a trader and love to take profits.. Also i cannot predict the future past the next bounce..
So while I am an awesome trader, I suck pretty bad at investing.. thats why my strategy is to just hold a little of everything that interests me... I do what im good at and trade, then I always keep some for the long term..
As far as my portfolio of coins go.. Im not comfortable anouncing my holdings.. But I will always be happy to share my trading knowledge..
Oh, and about your question of sizing your trades.. I think someone can easily trade 300-500 ETH without any trouble, on most large exchanges.. and thats 60,000 to 100,000 .. so I dont think scaling is much of a problem.. I dont even trade near to that size in ETH