Unless it's uneven and has tripping hazards, I'd probably just weed and add sand. I've helped lay paver paths before and it seems to me it would be a lot of work for the same result. If you do chose to re-do it, you might widen the path by one full paver.

I agree with Bride above. Sand to fill cracks and spray or pull the weeds.

I pretty much agree with the above comments. The long joints are a bit wide, but overall the path looks in plane. If you wanted to tidy up the long joints, you could leave the center course of pavers in place and butt the two side courses up to it. However, you'd need to remove the side courses and clean the weeds out (by carefully cutting) first WITHOUT disturbing any of the sand. IE, you must lift the paver very carefully and replace it by setting straight down, not sliding. You could try a couple to see if it's going to be worth the bother, before you remove a whole row. If it's not worth the bother, just remove weeds and fill the joint with sand as everyone says. If you want to change the grade for drainage, lift all the pavers and create a new sand base. Tamp the base, screed the sand setting bed, set the pavers and tamp after they are all set.

A QUALITY woven landscape fabric placed below the base will add stability, but it looks like you don't need it because all the pavers look in plane. It will NOT help you fight weeds.The way I take care of weeds is to kill them with glyphosate (Round-Up) and then apply Preen (per mfg. periodic schedule) to the path. It works quite well.

Wow, I didn't expect so many responses! Thank you all for taking time out of your day to help me out. Sounds like the polymeric sand route after weeding is the way to go. This should be a much easier job than I anticipated. I'll be removing what I can of the weeds by hand, spraying round up within the cracks to kill some of the deeper stuff and applying sand. As yardvaark suggested, I may also try and lessen the gap between the pavers in the long dimension. Should get around to this hopefully within a few weeks, have to find a few days of no anticipated rain. Finished pictures to come. Thanks again everyone!

Polymeric sand is sand with cement added. Many use it thinking it will be a long lasting solution, but it usually isn't. A paver path, unlike a solid concrete slab, has some movement from various sources: freezing, thawing, ground-swelling from moisture change and weight from traffic. A thin layer of polymeric sand between pavers hardens into a thin wafer, like a potato chip. It really has no strength to oppose the aforementioned forces and will break back down into sand and chips in not too long a period of time. It's ability to fight weeds is short lived. Figure that you'll need an alternate method of weed control not too far down the road. Another drawback of using it is that, because it has cement in it, this powdery residue will coat the pavers during the sweeping-in process, often leaving a haze/stain of cement on them. Because it's a thin coating, it will wear off over time. Trying to hurry it along with an acid wash will add wear to the paver surface so it's better left to wear off naturally.

Great info on polymeric sand, Yardvaark. The one bit I'll add is that it will also serve somewhat like grout between pavers, to stabilize them in position, at least in the horizontal plane. It certainly isn't a permanent solution, as stated, and also isn't much of a weed preventer. But with a properly prepared gravel base, and properly applied, it can help approximate the stability of a concrete slab without the permanence or expense. It is also permeable, so water can leach through the cracks readily.

My experience with the stuff is limited to the paver border/mow strip between my lawn and flower beds, but it has worked quite well for that application:

But sand alone does all those things.

Sand does those things and is permeable, polymeric is not.