If you go the 2m route, and want reliable simplex communications. On the new Ham radio market I'd personally limit your options to the FT2900 (75watts), IC-V8000 (75 watts), and the Kenwood TM-271 (65watts); on the basis they all offer more than 50watts maximum power output, which is a good starting point. You could also look into some used 100w Motorola VHF mobile radios and program in a few simplex frequencies, but if you're primarily looking at simplex you'll want the flexibility to move around frequencies with ease so that if you come across another conversation on your usual spot you'll have the ability to find a frequency not in use. Power to distance in VHF/UHF applications is an exponential relationship, and twice the power of a 40w mobile won't mean twice the range, but twice the power coupled with a good antenna system may make the difference of those last few miles needed to reach your buddies homes.
You'll also need to select your antennas carefully looking at the map considering if you're going to be in a line or spread out, an antenna offering a little more gain as Caleb mentioned, then you'll be increasing your ERP as well as your ability to pull in signals.
Higher above the ground is better but if you don't choose all the elements of your setup properly it may do more harm than good, look at the feedline and what the loss in dB is going to be over your given distance. You'll also need to consider anything you add in line (meters, lightening arrestors, etc.) and what loss it has. All of it boils down to the more of your signal that makes it to the antenna the more that antenna is going to be able to do with it. (On a side note that reminds me, invest in an SWR meter, start with the lowest power setting and make sure your SWR levels are low, even if it's advertised as ok, it's always a good idea to check SWR when modifying anything in the feedline, 10sec is cheaper than replacing a radio because something is amiss)
Also if you're selecting a higher wattage radio, when looking at your power supplies you'll need to know the Amperage draw of the radio, it's alot harder to find a power supply that'll handle 17-25 amps than it is to find one that'll handle ten or less, and my Ft2900 will draw 17amps when transmitting at full power. You'll also want to make sure you're 12v power supply puts out a true 13.8v not 12.0 or 12.1 or you may have some issues with it putting out less than the advertised power.
There's some equations you can look up if they're not already mentioned in your study materials that will help provide you a good theoretical guide so you should have some idea of what to expect, you can also find some software out there that will do the same and give you a map over your local terrain.
And something to keep in mind, while getting into radio with a few buddies is certainly a great way to learn things an get into it and stay active, however I'd encourage all of you to be sure not to limit yourselves to just that; there's a lot of ham radio out there that is available to you with a technician license, and even if it's just trying something one time, there is a lot of value to be had in the experience of attempting contacts via Satellite or the ISS, or building an antenna/power supply, checking into a net, trying out sideband, EME, CW, experimenting with APRS packet, developing fox hunt/radio direction finding skills (and with a group you can do a little triangulation too), in June get out on field day and have someone show you the added privilege of having a General or Extra License. Basically know what's out there and get a taste for it. Don't be afraid to branch out, it's a fun hobby; I'm constantly learning things, trying new things. It keeps my brain engaged and the hobby and my attitude toward it fresh.