I played a tournament not long ago with a bit different lizardmen army than planned, since for some reason I couldnt find the box with my slanns and stegadons! Old Blood, Carnosaur, sword of hornet, glyph neck,dragon helm, l.armor,shield. Skink priest, lvl 2, dispel scroll, blood statuette Skink Chief, terradon, l.armor,shield,spear,staff of the lost sun Scar Veteran, Cold One, l.armor, shield. G.W, BSB, amulet of warding 10x skink skirmisher 10x skink skirmisher 10x skink skirmisher 10x skink skirmisher 10x skink skirmisher 24 skink cohort, + 3 kroxigors. musician&standard 5 saurus cold one cav. huanchi blessed totem 3x salamander Ended suprisingly well with a good win over dark elves, high elves and beastmen. Games varied a bit, but the carnosaur did decently well(Slann would have been better tho). The skinks terrorized the flanks, the terradon chief took out some bolt throwers, chariots and march blocked well. Used the Cav with the scar vet on 1 flank with a few skinks, the carnosaur with skinks on the other flank, and the skrox block in the middle with salamanders. Pretty happy with the results considering its my first tournament in around 10 years.
Instead of the shield on your Scar Vet, to get a 1+ armor save give him the Dragon Helm instead of your Old Blood. The Old Blood already has a 1+ armor save being mounted with Lt Armor and Shield. If you want him to have the 2+ ward vs fire, give him the Dragonbane Gem instead of the Helm. The Gem will cost you the 5+ ward save because you'll have to lose the Necklace, but you could replace his Lt Armor and Shield with the Armor of Fortune to get it back. I think if you make all those changes, you end up with an extra 11 points to spend... and I would recommend investing that in the Venom of the Firefly Frog for your Scar Vet.
Cant you use the shield against shooting? But yes, those changes seems like good options. I ended up making a few mistakes with my magical items that got pointed out a few minutes before tournament began so had to shuffle around points last minute so ended up with whatever seemed best given the time.