So a God who is love must either save none or endeavor to save all? He cannot, in love, save some?
Why would he?
God created us in his image, Genesis 1:26-27 - unless you believe that applied only to Adam and Eve. He saw us before we were even born and knows everything about us, Psalms 139 - unless you believe that has limited application.
Mankind sinned, and the relationship with God was broken, Genesis 3. ALL have sinned and fallen short of his glory, Romans 3:23. The wages of sin is death, Romans 6:23.
Christ died for sinners, Romans 5:8 and for ALL, 2 Corinthians 5:14. He came to reconcile people to God, Romans 5:11; 2 Corinthians 5:18-20.
None of us can ever do anything to earn this reconciliation, salvation and peace, Ephesians 2:8-9.
So on what basis would God say, "I'll save you .... but not you" - a whim?
It wouldn't be because he hadn't created the people he chose not to save; Scripture says that everything was created by God, through Jesus.
It wouldn't be because the saved had done more good deeds than the non saved; Scripture says that we are saved by grace, not works.
God IS love, and 1 Corinthians 13:4-7 says that love is kind ...love always protects ... always hopes ... always perseveres. How is it showing love to say "you deserve death so you're going to receive it - but your sister/friend/parent/twin is going to receive eternal life and every spiritual blessing in Christ - just because I feel like giving it to them, and rejecting you"?
I wouldn't want to worship a god who behaved like that. How then do we preach the Gospel? Whatever people said, did or believed, God would save the ones he wanted to save.
If God chose to save none, would that be inconsistent with his love?
Mankind sinned against God.
As the one who was hurt and sinned against, God had the right to respond as he wanted. He chose to show mercy and give second, third 6th and 20th chances. When dam and Eve were ashamed because they were naked, what did God do; took the bloodied skin off an animal and made clothes out of it for them, Genesis 3:21. Their sin had consequences, and he punished them - but he clothed them to hide their nakedness as well.
Even by the time of Cain and Able, people were offering sacrifices to God. Moses gave them a sacrificial system, where the blood of animals atoned for their sin - and Hebrews says that without the shedding of blood there is no forgiveness, Hebrews 9:22.
God didn't have to do any of that - he would have been perfectly justified in saying, "you have sinned against me, I'm going to punish and kill you." He chose not to; he chose to send his Son to die for us sinners, Romans 5:8 - thus showing that he IS love,1 John 3:16. If God had killed people as soon as they sinned a) the world would be empty and no one would live for very long, b) there'd be no need for Jesus to have come, and c) he would show himself to be a God of wrath and anger - not that anyone would live long enough to see it. Why would Jesus offer his life as a perfect sacrifice for sinners - if God killed, and therefore didn't save, sinners?