I started playing again a couple months ago and did exactly what you intend to do as far as seeing the content without being concerned about the end game.

As Khat said any class combination will work. The mercs give you a great deal of flexibility.

I have several teams from the 40's to the 80's and everything I've tried has worked. My highest is a Pally, Dirge, Wiz and in many cases I can get by with a single healer merc but have a dps and tank merc available depending on the situation.

I've found that I prefer running with a healer merc rather than having one on my team. The Inq merc does an excellent job ( best healer merc in my opinion at least as far as the regular mercs ) and about the only time my pally will need to throw a heal is on a very bad pull or I'm in over my head level wise.

I've used both the SK and Pally mercs for my dps teams and they actually hold aggro better than my played tanks which I would like to believe is due to better gear rather than my lack of skill.

The dps mercs are both a blessing and a curse. They extra dps makes kills much faster but at times you'll feel like you're in a pug full of idiots. I've lost count of the number of times they have pulled groups of mobs without any input from me.

The only utility spell I couldn't live without is "evac". Saves lots of running around when turning in quest and picking up quest.

About the only thing I would have done differently is started a guild at the start rather than waiting. I waited until a couple weeks ago to start my guild and will have it to lvl 30 this week sometime (guild hall available at 30) . If you plan on tradeskilling with multiple toons then the harvest depot will save lots of time with transferring of mats between toons.