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 R730XD Server 2x E5-2690v4 2.6GHz =28 Cores 64GB H730 4xRJ45
$387.00
1U Supermicro Server 10 Bay 2x Intel Xeon 3.3Ghz 8C 128GB RAM 480GB SSD 2x 10GBE
$273.00
Cisco UCS C220 M4 1x Xeon E5-2667 V4 3.20GHZ 128GB DDR4-2400MHZ 2x 770W AC PSU
$129.99
Dell Poweredge R630 Server 2x E5-2620 V4 =16 Cores | S130 | 32GB RAM | 2x trays
$153.99
Dell PowerEdge R630 Server 2x E5-2640v3 2.60Ghz 16-Core 64GB H330
$182.65
DELL R630 SERVER 8 x 2.5'' 2X E5-2680V4 32GB RAM IDRAC ENT & NDC 2X 495W PSU
$169.95
Dell PowerEdge R730XD 28 Core Server 2X Xeon E5-2680 V4 H730 128GB RAM No HDD
$389.99
HP ProLiant DL380 Gen9 2U Server 24 BAY 2.5" Xeon E5-2680 v4 64GB RAM H240ar
$159.99
Dell Poweredge R720xd 2x Xeon E5-2670 2.6GHz 16-Cores 64gb H710p 26x Trays
$339.99
1U BareMetal pfsense opnsense Router Firewall DNS Server 6x 10GB Ethernet Ports
$149.00