It's a question of scale really.
If its super detail and super finish you are after, then nothing can beat 1:35, obviously! The work of 1:35-scale modellers are a constant source of inspiration, admiration and even envy for me
The amount of available kits is small though, even meagre when compared to the glut of WW2-material. We have for instance Tauro and EMHAR but their 1:35-efforts do look a bit dated compared with the latest efforts from, say, Tamiya. I've seen articles on very fine resin WW1 kits, but they are also few.
I am a 1/72-scaler myself. And the reasons are chiefly time, money and space. 1/72 scale kits are much cheaper and take up much less space than 1:35, and also you can finish a kit with quite reasonable results in just a week-end. And also: the amount of available 1/72 WW1 kits is MUCH bigger, especially if you want to do artillery and/or softskin vehicles as well. The quality of many kits are so-so, especially if you compare them with standard 1:35 scale kits, but quality is steadily improving even here. (1/72 scale AFV kits are in general getting better and better. Some of the new Revell offerings are in detail almost comparable to 1:35!) I can recommend you taking a look at my site (http://www.landships.freeservers.com
) where you can find both a lot of reviews of 1/72 scale kits, and lists of what kits that can be found. And there is more about than you think!
Botttom line: it's your choice! There are pros and cons to both scales!
All the best