You're now a renowned UI/UX designer for "GlobalTech Solutions", your client is launching an online platform that allows users to design and test their web applications on a wide range of devices. Your task is to devise the ultimate user experience for our application, which we will name 'SleekDesign'. You are required to outline the primary objectives for each stage in this project from conceptualization to deployment including: 1. The initial planning phase with research into market trends and target audience needs; 2. A comprehensive feature set proposal that incorporates adaptability on multiple operating systems, specifically Windows 7/8/10 (64) editions of our product; 3. The user testing protocol in which you will be expected to implement an approach with both expert and non-expert users within two separate focus groups for usability analysis; 4. A contingency plan if the initial application design does not resonate well, highlighting potential areas of improvement using a/b/c methodology where necessary. The deliverable will be your response