Baffled by the chunks

Smoke rings are pretty hard to achieve on the egg. So don't be overly concerned about that. Sometimes conditions are just right and you get that pretty ring but most times not. You can't taste the smoke ring so I quit worrying with it.  As far as your smoke taste, it sounds like you had the right amount of wood but maybe the chunks you added on top could have burnt off too fast. Maybe try mixing the same amount throughout the lump and see if that helps. 

You should have had more than enough smoke. I rarely use more than a handful of chips or equal volume of chunk.

Smoke rings only form while the meat is under 170F. If the meat is room temperature, and is thin like ribs, the surface will get over that temp pretty fast.

Smoke is deposited on the meat surface, and seeps inside some as long as the surface is only slightly moist. If the meat is too wet, the smoke just hits the water, and evaporates off as the water heats.

To improve both aspects, either rub the meat, and put directly into an Egg that is producing "good" smoke, i.e. blue and wispy, or rub and place uncovered back in 'fridge.

I suspect that your dome therm might have been a little off. At 250-ish, spares take more like 5 - 6 hours.

You might find this interesting. 

http://amazingribs.com/tips_and_technique/mythbusting_the_smoke_ring.html

How are you prepping the ribs ? Are you pulling the skin off the back  ? And are you using mustard prior to rub ? I'm not an expert but i think prep has a lot to do with it.

I can get a nice smoke ring on the Egg, but not consistently. As long as it tastes good, that's all that counts. This rib end was rubbed with mustard and spices and cooked indirect over a couple of apple wood chunks. 

Most posters are addressing the smoke ring, which looks cool but has nothing to do with flavor, but not the lack of smoky flavor, which you also mentioned.

What I've had the best results with, lately, for getting a more smoky flavor, is (a) no wood until just before putting the meat on.  I light the fire in one central location, no plate setter yet, let the temp stabilize, usually around half an hour, when it seems ready to go, then I put 4-5 hickory chunks radially around the fire so as the fire spreads it'll move into them, then add the plate setter, let it get back up to temp, then add the meat.  And (b) I find that I get more smoke at 250-275 than I do at 200, so I usually do low-and-slow cooks around there rather than around 200.

You can also get a "natural" smoke ring if you buy some celery powder (not salt) and mix that in your rubs.

Best smoke is TBS  (thin blue smoke ) .Smoke ring is like the cross hatch grill marks on a steak,looks only . Heavy white smoke and you end up with creosote. The best smoke is what you can barely see.