These bars your contemplating will add weight to the door. Check to see if you need to upgrade the hinges to compensate for the added weight. The hinges also need to have pins that cannot be removed since they will be on the exterior.
Therma-tru has fiberglass doors with a wood grain on them. They can be stained or painted. Wood doors properly sealed should not warp. Since they will open out it will be easier to paint the tops and bottoms. Painters rarely paint these. Unless you do, the door will expand and contract and possibly warp. Most doors have a warranty for various time periods, but they will not cover you if the door isn't sealed on all sides.
Ron

Therma-Tru makes GREAT doors--and yes, very pricey. Still, I'm not convinced that they aren't worth every penny. That said, 2 years ago we installed french doors with a transom in our old house and chose Pella. They're wood interior with an aluminum clad exterior, so no maintenance, and we did get low-E glass because they are west-facing. We like them a lot. I think that we paid about $1800 for the unit. Therma-Tru doors would have been about $2500.

We're very happy with ours.

People nearby being present and visible at all hours is the best deterrent, IMO. My street has one of the lowest crime rates in town though neighboring streets are high. A few of us work outside often, openly interact, and anyone who who visits our atreet can see that we are observing.

Instead of bars, which might make you feel like you're in prision, I'd consider adding Gates at access areas, if possible. Also consider motion-sensing lights outdooors, sited and aimed so they do not disturb you indoors at night. And a radio &/or lights on timers for when you are away.

Regarding plantings, keep it low near entries. Door and window areas are best left exposed so sunc an come in and trusted neighbors can see who comes and goes. Know your neighbors, and agree to look out for one another. (That does not mean inviting everyone into your house, however. Perhaps just chat, offer plants, and attend neighborhood meetings, at first until you know your neighbors are worthy.

Intruders can sometimes drop from an adjacent roof, so perhaps plan visibly spiky ornamental plantings below access risk areas? Just don't make it easy for them. (I can send Holly Tree and Rose Seed if they fit the space)

I wouldn't spend too much just on security. If someone really wants to break in - they generally can, so maybe don't spend much more for security than you think you might lose, or pay for an insurance deductable. A Dog On Duty sign might help in the right spot (but try not to make it too ugly!)

We have a French door in our office, and when we replaced the locks, we put in a lock that has a key-operated lock on both sides (as opposed to a lock on the outside and a turning knob on the inside). That way, no one could break through the glass and turn the knob to get in the house. This very thing had happened to someone we knew in the neighborhood the year before!

I know that this kind of system is dangerous in a fire, but in our neighborhood, we really felt that the odds were much higher that we would have a thief trying to get in. If you do put in this kind of lock, just be sure to keep a key nearby and tell houseguests where it is.

Hope this helps.

Oh, and one more thing... our locksmith (who is absolutely excellent!) had us put in an actual doorknob instead of one of those levers. He says that the levers wear out quickly. Since you are putting in a new door, I thought this might be helpful.

Thanks for these responses.
I went to tthe door place over the weekend - and liked the Marvin Integrity doors a lot - but they're much $$$.
I actually like the sliding version - but can't quite figure out how to make them more secure. Perhaps an outer metal door? If not, we may have to get an inner swinging door..The motion detector lights we're going to get. We do have a dog. Sign is a good idea.

I did see the therma-tru doors - and was fooled into thinking they were wood!
Another possiblilty...

Impact-resistant french doors (sold hereabouts for hurricane protection) are awfully hard to break through.