I oversee a ~1.4 million SF shopping center / retail portfolio and from my experience here are some things I see that may help increase your odds of landing a higher quality tenant beyond the basic demographics (income, population density, etc):
1. Physical location: Position of the center on the street. Is center mid-block or at a hard-corner of signalized intersection? Is the strip center parallel or perpendicular to the road? If perpendicular do the storefronts face towards oncoming traffic or away? These last 2 questions defy logic in my mind, but some developers have built strip centers this way.
2. Co-tenants: Who else is there? Chain store retailers are like sheep, and they do follow one another as many retailers have good synergies with one another. As you have all mom & pop tenants you may need to sacrifice a little more on the first deal to open up the door for other potential deals.
3. Physical condition: Beyond repairing any obvious visible physical defects, a fresh coat of paint, new striping in the parking field, and some basic landscaping improvements. Even if the center is all concrete, adding some planter boxes with flowers on the side walk will go a long way towards curb appeal.
4. ICSC: Join the ICSC, attend the ICSC trade shows and deal making events, make marketing materials geared towards retailers and retail tenant rep brokers. If you don't have the time for this, then hire a broker that does this.
4. Be a "Deal Maker": Know the terms of a retail / shopping center LOI inside and out, know what higher quality tenants look for, and know what you need to hold firm on and can bend on.
5. Be broker friendly: Most chain stores have strong relationships with tenant rep brokers. Have an understanding of CRE commissions and how to structure them appropriately.