As for capacity on no tails. Not a big deal at all. In fact im currently splitting time between a Komatsu Pc 200, and a Komatsu 128, depending on space available. The other night I set a 6ft diameter manhole with 6inch sides, 7 feet tall and a 12 inch bottom. I would say at 75% reach, no problem. The guys thought I was going to have o use the 200.
As for the grapple/thumb argument. Ive run both. I should say ive run both in the industrial demolition business. Ive said it before, bucket/thumbs are for home wreckers. Another one i like to hear is you cant move material or grade with a grapple. I get to differ. All you need is an I beam. Viola, you have a dozer.
Not looking down at anyones methods. Ive used em all. From using a grapple as a concrete processor, to using a bucket. The thing you have to learn with the bucket is how to pickup objects. Remember, tracks are your friend for this. Either pin a large object between the tracks and what ever your trying to pickup. Or in a pinch you can even use your tracks. Which is easier sometimes, because you can spin your tracks to "scoot" something into your bucket.