The Debian-Live approach also provides some good opportunities. First and foremost, the very easy remastering makes it efficient to run with no persistent store quite often. For instance, upon remastering, I just start without the store, and the image I run is union-mounted with the persistence file and copied&compressed. Then I have to boot something else to copy the new squashfs image in place, but that's all that has to be done outside the system.
Boot the new image without persistence, create a new persistence file.
For further adaptations, the new persistence file can be mounted in an instance run under kvm, programs can be added and settings tweaked for an eventual new remastering.
Storing the series of squashfs-compressed images, one can always go back in this process if needed.
DELL PowerEdge R730 Server 2x E5-2680v4 2.4GHz =28 Cores 32GB H730 4xRJ45
$284.00
Dell PowerEdge R620 Server 2x E5-2660 v1 2.2GHz 16 Cores 256GB RAM 2x 300GB HDD
$89.99
Dell R630 Server 2x E5-2620 V4 2.1GHz =16 Cores 128GB DDR4 1x 960GB 2x 1G 2x 10G
$210.00
Dell PowerEdge R730XD 28 Core Server 2X Xeon E5-2680 V4 H730 128GB RAM No HDD
$389.99
Dell PowerEdge R720 Server - 2x8c CPUs, 256Gb RAM, 128Gb SSD/3x900Gb SAS Proxmox
$340.00
Dell Poweredge R720 8x 2.5" Bay Xeon E5-2650 2.8GHz 8 Cores / 64gb No HDD
$114.97
Dell R730xd 26 Port SFF 2x E5-2697v4 36-Cores H730 128GB Server 2x SFP 10G ENT
$490.00
Dell PowerEdge R330 Xeon E3-1220 v5 3.0GHz 32gb H330 2x 3.5" Trays SVR 2012
$189.99
DELL PowerEdge R730 Server 2x E5-2697v3 2.6GHz =28 Cores 32GB H730 4xRJ45
$290.00
DELL PowerEdge R630 8SFF Server 2x E5-2680v4 2.4GHz =28 Cores 128GB H730 4xRJ45
$384.00