Most systems these days have EFI bioses, just create a 512M EFI partition[1] and put your kernel(s)(with a set kernel-command line) to EFI/Boot(bootx64.efi is usually the default being loaded). You don't need a bootloader at all(+you'll get a few s off of your boot time too). Many bioses let you choose a kernel at boot time, so you don't even have to play with efibootmgr[2] if running multiple kernels/OS's.
It gets more tricky if you want LVM root fe(which I'd recommend) - in that case genkernel[3] may make your life a lot easier, but even here you don't require a boot loader.
If you do want a nice(er) boot menu, just copy refind[4] to your EFI partition, configuration takes seconds and you can tune it very - VERY - easily
Also, folks @ #gentoo are very helpful, feel free to give them a visit if you are stuck.
And the last thing I want to add - you don't have to compile your binaries on your nb/slow hw, just setup a binhost[5] and compile your tailored packages on your beefy PC/server@work - you can then share them with your devices via http for example
Ok, last one - if you like elementary os, you can get the same look&feel running on gentoo, although it may take some hacks at this stage
[1] http://wiki.gentoo.org/wiki/EFI_stub_kernel [2] http://linux.die.net/man/8/efibootmgr [3] http://wiki.gentoo.org/wiki/Genkernel [4] http://www.rodsbooks.com/refind/ [5] http://wiki.gentoo.org/wiki/Binary_package_guide
..a buildroot micro-system running other distributions as overlays is also a nice time-waster and only a step away from gentoo(+ with lxc/docker there is a lot of long-hanging fruit to collect)
I don't remember last time I did an emerge world because of this. It's insane.
I first built a Gentoo install maybe around 2007, and had no problems up until the Grub install (however, I had done kernel compilations before). With Gentoo, the two hardest problems you arrive at _during installation_ are kernel configuration, and grub configuration. The former has now been solved with having great prebuilt kernels, or even just a way to use their configs. The latter may still be an issue, but once you wrap your head around it you'll be fine.
I haven't done a new install in a couple years - it just keeps running as-is, so I don't know about the state of affairs, but I would hardly doubt they got worse! I'm sure it's even easier than before.
A weekend is certainly enough time to build a base Gentoo system, and get enough packages installed to be able to use it for daily work.
If you have any problems I would be happy to help someone with a *ntoo setup! My email is in my profile if you run into any issues :)