I have a Shimano 105 10-speed cassette on my road bike, with sprockets 11-12-13-14-15-17-...-28 (I don't know by heart what comes between 17 and 28). I'd like to remove the 11, and put a 16 between the 15 and the 17 (because I dislike the gap between 15 and 17, and I don't use the 11 very much). I can find the sprocket: this one is for Ultegra, but I suppose it should work for my 105 too (http://www.rosebikes.nl/artikel/shimano-ultegra-cs-6600-10-speed-tandwiel-met-16-tanden/aid:119171).
Can I just take 11-15 off, put 16 on, then put 12-15 back on? Or is there something else I need to consider?
Alternatively I'm willing to buy another cassette instead, but I don't want to give up the 28. Are there compatible 10-speed cassettes available with 12-13-14-15-16-17-...-28 (or possibly even 29 or 30)?