>Also, you obviously don't think you need a rear suspension
>for road biking, and can get away without it for
>occasional off-road forays, thus I'm thinking hard-tail.
Suspension Seatposts are a great compromise for hardtail mountain bikes and a great compliment for road bikes.
For mountain bikes look at the Cane Creek Thudbuster. It has 3" of travel and can be tuned to the weight of the rider and/or the terrain in about 15 minutes by swapping elastomer slugs. You pay about a 1# penalty over the stock seatpost. It accepts any saddle. There are shims or specific seatposts for any bike.
For road riding it is hard to beat a Rock Shok 'in-line' mountain suspension seatpost. The 'mountain' seatpost has about an inch of travel, has a little tunability, and is wonderful at sucking up cracks, chipseal, and lumpy pavement. Worth Every dollar.
>I'm divided on the need for a front suspension but, heck,
>it is easy to add one later if you want it...
Possible, but Not cheap, and sometimes a challenge. Most likely you will need new cables and housing, possibly a new stem, plus bar tape. Adding a suspension fork will also change the geometry of the bike, raising the front end by 3+ inches, which changes the handling characteristics, and moves rider weight back a bit, also changing handling. If you are doing off-road, start out with front suspension. It's easier on your wrists, elbows and shoulders, keeps the tire on the ground, and makes for a better riding proficiency, as well as comfort.
>Personally, I'd rather have straight handlebars than
>curved road-racing bars.
Off-road - absolutely. Road riding - maybe. Unlike mountain biking where there is a lot of body movement, unweighting, shifting around, frequent standing, etc., road riding is pretty static. If you are riding more than an hour, having multiple hand positions is a very good thing. Moving from the shifter/brake hoods to the flats, to the center, occasionally to the drops, and back again alleviates a lot of hand and wrist issues. It also provides some relief to the shoulder and lower back muscles by getting them into slightly different positions.