I think you already know the answers to your questions, and possibly even the outcome :D
That said I think since you already have a nice assortment of gyuto's and a fair sampling of others why not add a cleaver?
Only real thought I had when reading your post was that it seems like you prefer some of the better or more highly regarded knives and how this would translate to the level of clever you would purchase.
I know when I first got into J knives I did so at an affordable level planning that I could always update to more expensive knives in the future if I was happy or impressed etc (which is exactly what happened BTW) and if it were me I would be looking at one of the inexpensive cleaver's like so many talk about finding at local Chinese grocery stores etc. as this would allow you to find out exactly what you think of using one without enough investment that it really matters.
Since a cleaver is something I have been considering myself since I found out I really do not have anything I like for chopping or splitting heavy stuff or bones etc due to the fact that the one I have that is from an old inexpensive set that though is "decent" because it was Japanese etc it is just too thin for the heavier jobs, and now I am looking at either a heavier cleaver or some old 10" woostie chefs etc. but like you I question if I really need a cleaver.
When looking at the attractive ones in the $150+ range I immediately say PASS as it is too much unless your just collecting etc and the low end ones seem to make more sense overall.
Then again for my intended use a old carbon "brute" that's been laying around in someones garage for years may actually be a better choice, but from what your telling us above I think you are looking at the opposite end and also think you may be right that it would be competing with your nakiri and ultimately it will be up to you to decide if you want to add to the use range of your set, or just add to your collection, or even if the Chinese cleaver or the nakiri would be better for your use.
Sorry but I do not have any experience or input on the others except that I agree that the kiritsuke from many mfg does look like a nice piece, but honestly have never seriously thought about getting one.