East of A1A within walking distance to the beach definitely adds significant value to any home on the island. However, any home on the island enjoys the close proximity of the beach -- just a longer walk if you live west of A1A. Since you focus on "value" I wonder if your interest lies with future resale or rental potential rather than personal preferences for a home. Historically there has been a premium on the residential areas surrounding the island resort area close to the boutique shops, restaurants, and close to Riverside Theatre, and the Vero Beach Art Museum. These properties provide the resort lifestyle where one can walk not only to the beach but also many of the area attractions. Oceanfront condos offer the carefree opportunity for fabulous ocean views. As another example, the Riomar area features lovely older and a few new homes, some on old oak-canopied quaint shell-and-sand roads.
However, if the home choice is for personal year-round or seasonal residence, you might prefer one of the many island communities that is more secluded and perhaps gated. Currently, there are deep price reductions in all price ranges in Vero Beach, including single family homes and condos on the island, on a home-by-home basis depending on the seller's motivation level from the numerous multi-million dollar estates to the beach cottages on the market.
Buying a home is part "logic and business" and part "heart and soul," so the value you are seeking will be a complex combination.
As an ABR (Accredited Buyer Representative) and CRS (Certified Residential Specialist) Realtor, I invite you to contact us or another Realtor to assist you in your search for the home that satisfies the complexities of your search criteria.