If you are certain that you can score well in XAT next year then you can go drop a year and try for XLRI. XLRI is widely reputed and offers great placement opportunities owing to its industry presence and huge alumni base. IIM brand name offers good opportunities but the new IIMs have many issues in terms of academics, infrastructure, etc.
The selection criteria of B-School changes over years. There are various parameters that are considered for the final selection, such as academic scores, work experience, CAT percentile, etc. Your 10th and 12th scores won’t do much to make your case and there’s a high probability that you will end up with the same IIM every year.
One of my friends was in a similar situation a few years back and he took admission to IIM Rachi based on the above logic.
But if you are hardworking, you can definitely make a good career at any institute. As for whether you should go for new IIMs or prepare another year for XLRI, that’s entirely up to you.