I hear you. I was like you for the longest time. I had an SE for 3~ years and I absolutely loved it. I researched and researched to find another phone with the exact same dimensions. Couldnt find anything. The thought of moving up to a bigger phone pained me.
I eventually bought the iphone 8 about 6 months ago. And my god, it is just as good if not better. The size that scared me so much? Turns out I like it even more. The speed has been great, and I never knew how much I'd appreciate the larger screen. Point is, I know where you're coming from. But trust me, the iphone 8 size still feels relatively easy to hold (I can still comfortably hold it with one hand 100% of the time), and I have 0 regrets whatsoever about the upgrade.
I eventually bought the iphone 8 about 6 months ago. And my god, it is just as good if not better. The size that scared me so much? Turns out I like it even more. The speed has been great, and I never knew how much I'd appreciate the larger screen. Point is, I know where you're coming from. But trust me, the iphone 8 size still feels relatively easy to hold (I can still comfortably hold it with one hand 100% of the time), and I have 0 regrets whatsoever about the upgrade.