Lack of standard USB on new macbooks

I am looking at finally upgrading to a new macbook. I currently use a 2012 15" and like the screen size as i often use 2 documents side by side and like it that way. I appreciate the inclusion of the HDMI port but cant understand why USBC is the only USB size when I will will have to add a dongle to suit many other USB based devices including a non bluetooth mouse i use all the time. I haven't seen a USBc mouse yet. For the amount of time I use an HDMI by comparison I'd rather have to use a dongle for that even though I am aware of the potential for signal breakdown using dongles. Anybody else see it as an inconvenience or am I the only one?