When I was doing my own investing I made up Notes for each stock or ETF I was following but simply used links to external sources such as two brokerages and several bulletin boards. A great resource was value forum an group of individual investors who post their own portfolios and "rules" of investment There is a low cost trial period (www.valueforum.com)
I think spreadsheets are much better done by the brokerages if you want updates on a portfolio. TBX would be better for aggregating news sources than financial data.
Of the brokerages for traders, options etc I would recommend Think or Swim from TD Ameritrade.
One of the things you DO NOT want is any errors in figures and I think following brokerage accounts is safer in that regard than transferring data elsewhere, where it is more readily hacked from your own computer.
So for example you might have a container DailyUpdates and then put in links to brokerage portfolios
Another for ALERTS or NEWS each of these could have child notes for individual stocks or ETF.s
Prototypes fori individual notes could control varying inputs.
If you are an active trader, day trader etc that is a whole different world.