I'm not exactly sure what you are talking about when you say "brokerage link".  I assume it's a way for you to invest 401k funds perhaps?

Regarding your questions.

I use Fidelity myself though my situation is probably a bit different.  I have an IRA (traditional), Roth IRA and a "regular" brokerage account with them.  Here is how it works for me.

I can buy or sell stocks, ETF's, mutual funds, REIT's etc. in real time (for the most part).  The "waiting until 4:00 PM EST for a trade to settle is usually tied to mutual funds only.  With an ETF or a regular stock the trade happens whenever you want it to happen.  As far as fees, it depends on what you are trading.  Most mutual funds along with many ETF's are going to have a fee associated with them.  Fidelity does offer some that have "no fees" depending on the circumstance.  As an example there might be a fee charged if you hold the security for less than say 30 days.

Pretty much any stock on the three major exchanges is available for trading.  Some ETF's might require additional paperwork to trade only because Fidelity is more-or-less making sure "do you really want to do this" kind of thing.  These are generally slightly more "advanced" products that basically have 3X the risk.  As an example you can buy an ETF that tracks the DOW at 3X.  In other words, if the DOW goes up 100 points the value of that product goes up "300 points".  On the downside, if it goes the other way you lose that much more.

It works the same for all 3 of my accounts with the only difference being the tax advantage of the IRA's vs. my regular brokerage account.  With my regular account any gains I make when sold are subject to a capital gains tax.

I STRONGLY recommend doing your diligent research before venturing into this.

As far as stock predictions, I rode the Boeing and tech stocks/ETF's over the past few months.  For the most part I have taken profits and kept a relatively small share in each of the investments that I made.  I think the market overall is going to be rather volatile until the election.  Finding the one stock or sector that might make a 25% gain over the next year is in my opinion a fool's game.  Right now I just look for value as far as dividends.  It all depends on your age, level of risk that is acceptable, etc.  My advice is to look beyond the next year and more towards 5-10 years.

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