It does already. Thana made those especially for the installer.
IMO once the installer correctly sees enough 'free space', it should offer up to use that space in the best way required for an Elive installment.
If it cannot, it should point to the 2nd Howto on manual partitioning or have it running alongside in a webwidget.
Late to the party - But I had to reply. Please keep in mind the written word is NOT ALWAYS received by the reader in the same tone the author was attempting to project. Missing voice tone, inflections & facial expressions convey much more than many of us realize until we're caught with foot-in-mouth. Expressed with real experience;
Anyway, I have converting normal everyday Windows victims for decades. In addition, due to my age & 20 years ago was invited to guest announce for an AM radio show & have been on air almost weekly since, the majority of callers & clientele were/are "baby- boomers". The boomers, at least here in the US were severely neglected & written off as too old to change. Especially when they went out to buy hardware. Oh the stories I could share.
My point here is most suffer from sub-conscious mind set that all the children & grand children are smarter than they & developed an almost "BLOCK PREVENTING THEM MAKING BIG LEAPS". Without providing a simple to use "Dual Boot"allowing them that safety net, just in case of emergency &/or completing a task on time, I believe at least HALF (50%) would NOT have made an attempt to get away from the "Evil Empire"!
As to the remark that seems to dominate - "The noob's will NEVER BE SUCCESSFUL INSTALLING A DUAL BOOT. I must with all do respect disagree. Hasn't anyone here picked up an .iso from Linux Mint (prefer Xfce) lately??? I have actually walked NOOBS through the process over the phone with no visual access whatsoever. This even included Mirroring the original HD & upgrading to a SSD HD. If one can 1st get the BIOS configured and then provide step-by-step instruction LM falls together. Even with customizing the grub menu. I have no doubt by including a "relatively easy install process" that can empower the apprehensive noob suffering with a severe lack of confidence just because it is all UNKNOWN and nothing else. Once that noob does it on his/her own they run out and attempt to convert everyone they know or anyone that will listen. I have seen it first hand and it is a beautiful thing!!!
Over the years I have developed some strong opinions regarding support & the mistakes made by big biz. Most of the biggies are doing it (or should I say NOT DOING IT?) - COMPLETELY BACKWARDS!!
I apologize if I got too lengthy. I do that sometimes & it's getting late here so I'll have sign off.
JMHO,
Be well,
0bWAN