Not sure if this is the quilt you’re talking about or not, I bought my kit from Blueprint about 2-3 years ago. IMHO, if you want to enlarge it I would pull out the graph paper, and graph out complimentary blocks to add some additional pieced borders. This would alleviate your concern of too many solid borders and allow you to get it to the size you need. Star blocks, log cabin blocks, delectable mountain, etc would give you the best size options for your additional borders and look well with the overall design.
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