That will depend on the extra benefits that your organization can get from being ISO 9001 certified. Do your company’s target customers value ISO 9001 certification besides ISO 17025 accreditation? It that is so, perhaps getting ISO 9001 certification could be useful.
Just implementing ISO 9001 on top of ISO 17025 accreditation can be useful if used by top management to introduce the business flavor. ISO 17025 is about technical competence. ISO 9001 has several business-related topics not included in ISO 17025 like:
Context of organization and interested parties
Quality policy and strategic direction
Monitoring and measurement that can be very useful together with the use of the process approach.