I don't believe this actually works - you use the Maximize when rolling damage, not when casting the spell. So you can spend the Channel Divinity to maximize a single bolt, but not every bolt for the entire spell.
Yup I think I was wrong on this one.
OK evaluationg the death clerics. You can use chill touch on two targets as long as they are withing 5' of each other. This is from level 1 so may not work all the time but the death cleric now has the best at will ability in the game short of a war cleric and level 8 light and knowledge clerics and even then you can hit multiple targets. That is a good ability. YOu need a decent wisdom score and you are a cleric.
Touch of Death. This is in effect a smite attack. I don't think it is as good as the war clerics +10 to hit one let alone the light clerics radian dawn. 5+cleric level damage on a melee hit loks good BUT it has to be a melee attack on a class that doesn't get heavy armor and seems to be very MAD at this point.
Default stat array
str 13
dex 14
con 12
wis 15
int 8
cha 10
You will probably need to make your stats look something like this to have a reasonable AC. This gives you AC19 in the best medium armor which is decent enough. Ideally you want racials to get that strength and wisdom up so variant human I suppose.
Str 14
dex 14
con 12
wis 15
int 8
cha 10
You could also go for a wood elf and key things of dex. This gives you speed of 35 and you can use a rapier keyed of dex and AC 19.
Str 13
Dex 14
Con 14
wis 16
int 8
cha 10
This makes you less squishy than the 14 strength option at the cost of a feat (warcaster, tough etc) so seems a bit pointless unless your DM doesn't allow the variant human.
You could also dump strength and run around in studded leather+shield but your AC will be 17 at best and unlikely to be buffed.
If you have a moderate dex score (14) you can also use bows reasonably well regardless of race so that may be a better option some of the time than sacred flamne or chill touch.
The class seems a bit MAD to be honest to use all your features to some extent. Light cleric can easily sit at the back, use radiant dawn, flare and throw fireballs it doesn't have to melee unlike this one. Gauntlets of Ogre power would make this a lot better and you can get some in LMoP.