Normally, the AI loves to throw "Discredits" at you, any time you start influencing a sphere member of theirs or one of their own targets. That essentially "wastes" 25 Influence points with no LONG TERM consequences to you, merely a 6 month delay while you do something else instead (unless you're REALLY close to kicking them out, in which case it may pay to suffer the penalty and continue). Sometimes, it pays to wait until your rival is in an Influence duel with some other power over another country, and then make you own move. If not, draw their Discredit, then start influencing another country in their sphere, so they concentrate on that instead of replacing the 25 Influence. 6 months later, you've got a free shot at boosting your own Influence until they can rebuild enough of their own for another Discredit.If you manage to knock Saxony out of Austria's sphere, Austria often (not always) gives up the Influence-pissing contest. Try not to allow them to build up 50 or 65 points of Influence, by distracting their attention elsewhere, otherwise they can throw nastier stuff than Discredits.
Once you achieve control, build up 65 points, which can be used to BAN a threatening rival for a year. Normally, I'll let a rival get up to at least 80-90 points of the 100 needed to kick me out of control, and THEN ban them. It costs me 65 points to ban them, and they lose 80-90 points, and can't even begin to rebuild those for another year. Hopefully, they'll use that time to bug one of your other rivals. As long as you're not ACTIVELY putting Influence points into a country, the AI will ignore you, so that's exploitable. There's also a tech that increases your rate of Influence, which is a major help to Prussia in particular.
As said in previous posts, you don't really NEED to fight any wars to form the North German Federation, and don't need to fight at all until you take Alsace-Lorraine from France to form Germany, although an early war against Denmark can net you the entire peninsula, leaving Denmark with a few islands, and you've got ages to burn off the Infamy. The rest can all be done diplomatically. Try playing it as a diplomatic/economic game first, and a war game second, and it's a lot easier. Peace and prosperity beats ending up with a war-torn country that managed to grab some small patch of land with a hostile population and no important resources. Save MOST of your wars for colonial conquests of uncivilized countries, which cost you less Infamy and are far less destructive to your own population. It's primarily about the balance of power and influence in Europe between the leading countries, so you need alliances of your own and sphered countries to compete against the coalitions that will form against you. Taking on the rest of the world solo is definitely doing it the hard way.
