I assume by adding to it you mean adding in data files. And I would kind of agree with that to some extent (I actually mention that above, even.) But part of that is also what gives it a pretty high level of flexibility in what can be done with the program that can't be done in the others. It's one thing if you just wan to add some piece of equipment or the text of an Edge (and not necessarily all of the effects of that Edge), which to be honest is actually pretty easy to do in the Editor for HL as well as those other programs (and yes, other than Savage Outfitter, those are the progs being alluded to.) It just looks harder because of all the other options, which you can always just ignore.
However, having all of those other options, the ability to modify the stats on your sheet, or even conditionally do so if you are using HL at the table, the add other effects and so on, is an ability HL just has available right up front. Sure it's got a steep learning curve for doing that and the documentation can be more than a little cryptic (especially for folks with no real programming experience) but at least you've got several of us here who are active enough on the forum to try and help folks get over that hump, and some of the folks with Lone Wolf who check in here occasionally as well to give some of the really in-depth help if we get really stuck.
WCC may still be in beta, but it completely missed the MAIN selling point of its Kickstarter, that it would read any SW PDF and import it with all modifiers built in. It can't do that at all, so it's being done manually. And it's currently missing any good way for the customer to manually make their own stuff up, at least not well. Worse is that it is NOT in Beta, not at all. Current release version is 1.0.2. That 1.anything means it's the final release version, not beta, and no place that I could see on their site clearly defines the product as Beta.
Savage Outfitter is... well, barely a character creation program, IMHO, but I haven't bought it because it just looks abandoned and not really well done, I don't think. So overall I cannot give a fully informed opinion on it.
So to me the big competitor here is MetaCreator. Which to me has it's plusses (which, in part, you note but I also think you don't get all the functionality of adding something like a custom race that HL can do) and minuses which made it a big toss-up when I was originally deciding which one I really wanted to use for my gaming group in the long run. Now, with all of the data files that are now available for Hero Lab (and now that I have gotten past the biggest hump of working out how to make things for HL, knowledge of which I've tried to share on this forum) I think HL is hands-down superior to the other options.
Are there still issues with HL? Absolutely. And when I find them I try to bring them up in the threads on this forum for those things. Do they get fixed fast? It kind of depends on the issue, but generally no. They do tend to eventually get fixed, though, but I think we have to realize that for Lone Wolf their Savage Worlds line probably doesn't even hold a candle to the money they make on Pathfinder, so that's going to be their priority, period. That can be a bit frustrating, certainly, but as far as I can see it's still getting us more content and capability than any other character creation solution for Savage Worlds out there.
So there is a bit of a hump to get over to use HL well, but in the long run it's proven, for me, to be a worthwhile effort. We just need the kind of documentation for really using the editor (maybe even some tutorial videos) that they started on for their Wiki for a full on game system. Too many folks (including myself, originally) get confused by that Wiki thinking we'd need to duplicate a game system in order to make a data file, when we just needed to make a data file and set sources on it to help keep the things we do separated when needed. Stuff like that.