btw: Other than the fact that you can change bladders, what is the difference between a back inflate bc and wing? Isnt a back inflate bc a wing with a fixed harness that cant be removed? How would BP Wing give a better profile / more trim etc?
Mostly the difference is the plate and harness. The back inflate Bc's have the pockets, quick release straps (although you can get these for a BP) and more padding.
A BP tends to disperse some weight across your back allowing you to put less on your weight belt. This allows you to balance your rig.
both will help float you in a nice trimmed way if you set them up, my Ranger has trim pockets at the lower back for added adjustment.
My Ranger is NOT as compact as the other 30 lb BP/W system I have. Both have integrated weights (Apeks wtx system). The Ranger was about $700 and the Apeks was $530.
A jacket BC will be cheaper.
If you only plan to put a few dives in each year then investing in more expensive gear is probably not the best choice. Like going all in on some cell phone that you make one call every 6 months on.
Another consideration is storage and what will happen over time. If you dive infrequently and your gear hangs around, you will probably find it will not last as long as you think or want it to. You may only get 20 dives on your BC if it hangs in a closet for 5 years and gets 3-4 dives a year. this may be due to UV exposure, drying out, construction etc. If you can handle that before you need to replace components and such then it would not be a problem for you.
For travel, you have the BP to add as weight (about 6 lb if stainless) but you can put this on the bottom of your bag to protect interior items and the wing in the middle.
If you plan on lots of travel diving, I would get what is most comfortable and affordable for you as you will be diving it lots.
My buddy dove a nice jacket BC from TUSA and when it wore out he switched to a BP/W after several tests and likes it better than the jacket style, my first BC was a jacket style then a back inflate and then a BP/W style. We do, however, dive cold water, dive drysuits and have big gloves on. The pockets and other things in a jacket style BC go unused for our style. If you use pockets and like storage then that is another thing to look at.
Hope you get what you are looking for.