I have a fondness for Alberg designed boats. I sailed a 22’ Sea Sprite solo to England in 1974 and that is an Alberg design. I also sailed a 27’ Vega to England a few years after that. The Vega has less room then the Alberg 30 and the Alberg 30 has more owner support in the US then the Vega. The Triton of course has less room then the Alberg 30 so does this mean the Alberg 30 would be the best choice. I have sailed all three and they are all easy to single-hand and all are more then capable of doing trans-ocean sailing with proper preparation.
You won’t go wrong with any of the three if they are in good condition but the 30 has the best support and is the fastest and roomiest of the three. It would be my choice under the circumstances.
All the best,