Why should one not disabled person need to instal by default the accessibility options of Ubuntu. Fortunately most people do not need them at all. It is great, that the OS supports people with disaeses accordingly - but it is not necessary to bloat a system by default with this stuff.
From what I understand, the install ISO (excluding the server and alternate installer) actually uses an image of sorts, making it very difficult to "pick and choose" which packages get installed. This is why the alternate cd is required when upgrading via disk.
I prefer to have a clean system with only things on it I really use or need. Accessibiliy tools are (among other software preinstalled) the less usefull stuff for an average user on the system. There is no reason to have them by default, while important things are missing (like a partition manager or connectivity protocols to access samba / nfs shares)
Or do you have a wheel-chair un your car trunc all the time or special pedals or other accessibility things installed - just in case, while the transmission gear is optional?
My proposal is to give users a choice what to install and what to leave on the cd. When i make a fresh install of my system due to major releases I have to wait a long time for downloading tons of software and afterwards spend a half night deinstalling half of them just because there is no option to disable this stuff.
On the other hand tools needed (and available on live CD) have to be APT-GETTED from the internet. Really necessary basic functions on the other hand are completely missing.
Just let users choose what to install - for dummies not knowing what they want you can offer preselected packages. I would prefer to have an option to opt-out packages before installation instead of removing them one by one later on.
You mentioned windows setup, that is installing accessibility tools too. That is right, but windows also installs a complete os with networking support and management tools for hardware, services, disks, security etc. in contrast to Ubuntu.
why not calling software center like application on installation to (de)select the packages one want to have.