Rearrange a Class Diagram Items Prepared By Microsoft Visio For a Better Look

Hi, I have a class diagram drawn using Microsoft Visio. I want to submit the view of the class diagram to a scientific article. Confidentiality of the project document is very important. In its current state, when I put the existing class diagram into Microsoft Word the classes look very small, and unreadable, thus, I also have to add parts of it into three separate figures which makes 4 figures in total which I do not want. I want to show the exactly same class diagram in a smaller space, more readable and a more attractive way (by attractive I mean selection of colors, readable text, clearly separated parts). Using only 1 Figure is targeted but if it is not possible we may discuss using two Figures at most. The designer should deliver me the project file (not just picture) so that I may rechange the text and other things later (if required in the future). I am open to other freeware or open source products. It doesn't have to be on Visio. The designer should have good graphical skills. More than one software can be used if necessary. I will submit three sample class diagram pictures here to clarify the things. I will share the actual file after deciding on a freelancer. The actual file is not very complicated and has very little text on it ( only the class names with just a few attributes for only some classes)