Seeking advice about the best ecommerce platform -- 2

I sell virtual goods and services for online games since 3 years on various sites but I never owned my own so I don't have experience or much knowledge about how ecommerce works. PRIORITIES: Ease of use > Speed > Functionality > Appearance (minimalistic graphic) That said I'm looking for somebody to analyze my needs (will send 4 pages long specification after initial vetting) and advise me about which platform will fit them the best (and why). You should also give me some tips and ideas about said platform, that will help me to design it properly and/or choose the right developer (for example if needed extension already exists or what product layout will be the best for SEO). I want to spend up to 5000$ for the initial site and then keep improving it. Requirements: - vast experience with creating/designing shops with the most popular platforms - very good SEO knowledge (from code pov), there will be a lot of custom functions and similar (for the customer) product presenting options may be totally different for a robot, I need to know SEO perspective for those choices Please write 1-2 sentences about your experience with above requirements and what are the top 3 solutions you usually recommend to your small/medium clients.