The /etc/X11/xinit.d/vram_tweak or the new LL_VRAM_MB variable in the cool_vl_viewer wrapper script ? Both shall work equally well with the Cool VL Viewer, but only the first trick will work with other viewers.
You really should not bother... Intel GPUs are not powerful enough, period.
The feature table shall not be modified: it is just a list of presets that correspond to the default settings for the different GPU classes (themselves defined in the GPU table). You can always override those settings at run time (via the "Preferences" floater, "Graphics" tab): if a particular setting is greyed out, it's just that your GPU and/or driver do not support the associated feature and no amount of tweaking will change that fact.
Indeed...
According to
NVIDIA's specifications for the GT 730, there are very different models, ranging from only 96 CUDA cores (insufficient) to 384 (might work)... I can't tell for sure, since I did not try it, but I personally won't try running a viewer in ALM mode + shadows with anything less powerful than a GTX 660 (for ALM without shadows, a GTX 460 can do it well enough), even more so if you want to enable SSAO as well. Your best bet is to give it a try before buying it, or to make sure you can exchange the card for a more powerful one (if you buy online, depending on your country regulations, there's a retraction delay during which you can return the goods you bought if you changed your mind about them) should it prove too weak.