As a versatile software developer well-versed in C++, Java, and Python - the three languages you consider most suitable for this project, I would be a valuable asset to your speed typing software initiative. Moreover, my deep understanding of AI and its various applications coupled with my experience in crafting innovative solutions, will provide an added advantage in optimizing your software's performance in measuring typing speed.
Furthermore, having honed my UI design skills over the years, I can assure you of a not just simple but aesthetically-pleasing and user-friendly interface that aligns with the feel and intent of your software project. Having previously designed similar interactive interfaces which have garnered positive feedback, I truly understand the power of a good UI and will ensure yours enables easy navigation and visual engagement.
Lastly, speaking on the actionable demands of your description- being English-fluent myself definitely comes as an advantage for item one; my comprehensive understanding of typing speed calculation methods is sure to accurately reflect candidates' words-per-minute scores and accuracy percentages. In a nutshell, with me you are not only choosing proficiency but also innovation, understanding, personal commitment to keeping up with this fast-paced industry, and a knack for remarkable end-results. Choose me for reliable and effective Speed Typing Test software.