Use a disk image for Link2SD's 2nd partition

Well, this question is targeted for those few devices without support for an external SD card as well as merged storage, for example my Micromax Canvas Knight A350. I thought this up today: If we take a QEMU disk image file (.img), set it to static with a size for, say, 4GB and format it to ext2 and copy it over to the Android device's internal SD card, can we mount it as /mnt/sdcard2 or something similar as a loop device (it appears that loop device mounting is possible on stock Android 4.0.4 and up, at least for some Samsung devices)? Secondly, will this work with Link2SD? Context: My device, as mentioned above, has a 2GB /data partition which is fast running out. I thought this up as a last-ditch effort to extend its lifespan (because it has 25GB /sdcard0 partition`, and I don't use more than 12GB of it), and would like to get the theory of this validated or refuted before I go about trying this on my device. **NOTE:** Any alternative suggestions, such as FolderMount (kindly suggested by @Izzy in chat ), are also welcome if these are accompanied with **proper usage instructions** for this specific case, that is, link folders from /data to internal SD. Side Note: Not currently considering FolderMount as it's advertised for internal SD to external SD linking, not /data to internal SD linking.