Toe clips provide an entirely, and extremely, different feel to cycling. You can be very securely connected to the pedal by pulling the straps tight. And you can pull the straps loose tight, snug tight, very tight, extra tight or bear trap tight, however you like depending on your mood, location and terrain. You can nuance your ride in ways that cleats prevent.
When I used cleats, I lost the best of what clips provide. When I rode in cleats, I got bored and missed the process of pedaling. I missed choosing and feeling how the toe clips held my feet and I missed choosing and feeling the give or rigidity of the hold while pulling back or up and while pushing forward depending on where my foot was in the rotation. Yes, in toe clips you can indeed muscle 360 degrees of the rotation. I do not think I loose 15 percent because I can use all my strength at any point in the rotation. Maybe a very small percent of energy is lost to the flexibility of clips, even when they are very tight, but I am happy to give up a tiny bit of efficiency to have the comfort and adaptability of clips.
In a way, clips are like an equalizer on a stereo. In both cases, you can make severe, moderate or slight adjustments so the feel is just perfect and then adjust again later for a different perfection. Another analogy is that using clips is like being embraced while using cleats is like being grabbed. It is important, though, to use steel clips and leather straps. Nashbar had them cheap a while ago. Maybe they and others still do. I use them. Plastic clips and or straps have no capacity for subtle and supple adjustment.
For shoes, I use road shoes with hard plastic soles with nearly no flexibility. That stiffness is great so I just took off the cleats so the bottom is flat. There is a very small plastic tap on the sole at the toe. It is like a very mini cleat that catches the front of the pedal so, when my clips are tight, I do not slip out. When the clips are loose, I can still pull up and, even, up and back at the same time so I don’t slip out. Such nuance. I like that aspect of cycling. Another option would be to have a cobbler glue a thin, flat, not treaded, piece of rubber on the ball of the sole for traction on the pedal.
To fit into the clips, I cut off one of the Velcro straps of the shoe so the shoe slides unobstructed into the clip. Tri shoes with only one strap would not interfere with the toe clip at all.
I wish they made road shoes for toe clips, but I can live with making my own modifications. What I really wish is that they made shoes wider. Is it really necessary for shoes to be so narrow, especially for us tourers? Do other people find them so uncomfortable? Has anyone found wide road shoes?