Everyone's taste is different. I 've had excellent gumbos which included either chopped tomatoes or tomatoe paste, with or without "okra" ( African word for Gumbo). Tomatoe paste should not effect the roux's color especially if added after roux is cooked.
The Best Andouille I've found was purchased from Bailey's in LaPlace, LA. Jacob's World Famous Andouille, located 1 block down the Hwy from Baileys, has artificial preservatives to allow shipment to all parts of the globe. Bailey's has no artificial preservatives, except for the hardwood smoke, which means you'll have to find a friend or family member to ship it to you.
I've also made rouxs in 10 minutes or less. The trick is to get the oil to its smoke point in a dark iron skillet or a porcelan coverd/clad iron skillet or gumbo pot. You have to have all your vegetables chopped ( Trinity - onions, bell pepper, celery plus chopped/minced garlic) to quench the roux so that it doesn't burn.
The procedure: Add oil to hot iron skillet (temp should be 375-400F). Recommend using peanut oil which has a high smoke point. Premeasure flour, and begin wisking in 1-2 tabs flour into hot oil until the flour begins tourning brown. Continue wisking in flour until all flour has been added. Remove hot skillet from burner, continuing to wisk until color of roux is a dark chocolate. Add chopped/diced vegetables immediately to qiunch roux and continue stirring mixture with a slotted spoon ( wood preferred). Once all vegetables are thoroughly mixed into the roux, reduce burner temperature to 325F, and place pot/skillet back onto burner. Add chicken stock, etc. and continue preparing gumbo.
Oiless roux can be prepared using the same iron skillet, wisk, and flour. Warning: you must add flour 1-2 tbs at a time and wisk till a nut brown color ( cinamon) is obtained . Once all flour is added and wisking yields a cinamon color, remove pot from burner and sieve/aerate/cool browned flour to stop it from cooking/burning. The browned flour should not contain any burnt pieces or clumps which will impart a "burnt, bitter" taste. Store any unused browned flour in an air tight container for later use.