With the distro I use, you can disable some things you can't in a binary based distro. That's one of the things about a distro that you have to compile yourself. Take Firefox for example. This is the options for it.
[ebuild U ~] www-client/firefox-44.0::gentoo [43.0::gentoo] USE="dbus ffmpeg%* gmp-autoupdate gstreamer gtk3 hwaccel jemalloc3 jit startup-notification -bindist -custom-cflags -custom-optimization -debug -gstreamer-0 -hardened (-neon) (-pgo) -pulseaudio (-selinux) -system-cairo -system-icu -system-jpeg -system-libevent% -system-libvpx -system-sqlite {-test} -wifi (-egl%) (-minimal%*)" LINGUAS="-af -ar -as -ast -be -bg -bn_BD -bn_IN -br -bs -ca -cs -cy -da -de -el -en_GB -en_ZA -eo -es_AR -es_CL -es_ES -es_MX -et -eu -fa -fi -fr -fy_NL -ga_IE -gd -gl -gu_IN -he -hi_IN -hr -hu -hy_AM -id -is -it -ja -kk -km -kn -ko -lt -lv -mai -mk -ml -mr -nb_NO -nl -nn_NO -or -pa_IN -pl -pt_BR -pt_PT -rm -ro -ru -si -sk -sl -son -sq -sr -sv_SE -ta -te -th -tr -uk -vi -xh -zh_CN -zh_TW"
The USE= part is things that can be enabled/disabled. The "-" sign means I have it disabled here. The other stuff is language support. If you don't need a language, disable it. As a example, I didn't want Firefox to use sqlite. I don't need it, even tho I have sqlite installed here for other things. I have it disabled here. I don't mind other things using it locally but I didn't want Firefox to use it. That may be one of the things that you wouldn't want either. Thing is, if you use a binary based distro, they may have it enabled and no method for you to disable it. You don't have that option. Of course, about:config may allow you to disable some things too. You may want to google up on that option as well. That is if you use Firefox.
While I'm not quite as privacy oriented as you are, I do understand where you are coming from. I think there is to much hocus pocus going on that we are not aware of too. It's one reason I use Linux to begin with because at least it is more secure than anything M$ makes. My biggest concern is when I visit financial type sites. That's when I'm a bit picky about privacy.
One thing I do here as far as someone hacking in, I put a router between my modem and my puter. I rarely have more than one puter going here so I really don't need one as far as networking goes. However, it does put one more thing between my puter and the internet. Basically, they would have to get past the modem and the router to even get to my puter. Since I don't store important info here, I have no idea why a person would want to spend the time doing all that. Also, my internet is not that fast so even doing a search of what I have here would take a while and likely be noticed by me since it would slow down other things.
My hope with these posts is that it will give you some ideas. It just may be that something I posted will cause that light bulb to come on and a google search later, you have found the Grandma of all solutions.